{ "$schema": "https://json-schema.org/draft/2020-12/schema", "$id": "https://quantcalc.app/docs/federal-tax/federal-tax-api-schema.json", "title": "QuantCalc federal income tax API", "description": "POST /api/federal-tax: validate a request against #/$defs/request; a 200 body has the shape of #/$defs/response and a 400 body that of #/$defs/error. Generated from the request parser's field table. Keys are matched case-insensitively by the API; this schema lists the documented spellings. Checks that relate two fields (spouseAge with filingStatus mfj) are listed under x-errors with the exact 400 message. Reference: https://quantcalc.app/docs/federal-tax/api/", "engineVersion": "1.2.0", "taxYear": 2026, "$defs": { "request": { "type": "object", "description": "The request body: one 2026 federal return. All amounts are annual US dollars. A key that is not listed here is refused with 400: the engine does not model it, and a figure that silently left it out would look complete.", "properties": { "filingStatus": { "type": [ "string", "null" ], "pattern": "^(?:[sS][iI][nN][gG][lL][eE]|[mM][fF][jJ]|[mM][aA][rR][rR][iI][eE][dD]_[fF][iI][lL][iI][nN][gG]_[jJ][oO][iI][nN][tT][lL][yY]|[mM][fF][sS]|[mM][aA][rR][rR][iI][eE][dD]_[fF][iI][lL][iI][nN][gG]_[sS][eE][pP][aA][rR][aA][tT][eE][lL][yY]|[hH][oO][hH]|[hH][eE][aA][dD]_[oO][fF]_[hH][oO][uU][sS][eE][hH][oO][lL][dD]|[qQ][sS][sS]|[qQ][uU][aA][lL][iI][fF][yY][iI][nN][gG]_[sS][uU][rR][vV][iI][vV][iI][nN][gG]_[sS][pP][oO][uU][sS][eE])$", "examples": [ "single", "mfj", "married_filing_jointly", "mfs", "married_filing_separately", "hoh", "head_of_household", "qss", "qualifying_surviving_spouse" ], "description": "single, mfj or married_filing_jointly, mfs or married_filing_separately, hoh or head_of_household, qss or qualifying_surviving_spouse (any case). A qualifying surviving spouse (§2(a): the spouse died in 2024 or 2025, a dependent child lives with the filer, not remarried; the caller asserts it) files on the joint brackets and standard deduction with the single Social Security base amounts and senior-deduction threshold, and has no spouseAge.", "x-whenAbsent": "single", "x-relation": "The return's filing status: the brackets, the standard deduction, the thresholds.", "x-limits": "One of the nine strings, any case; null = absent. Anything else: 400 naming the field." }, "filing_status": { "type": [ "string", "null" ], "pattern": "^(?:[sS][iI][nN][gG][lL][eE]|[mM][fF][jJ]|[mM][aA][rR][rR][iI][eE][dD]_[fF][iI][lL][iI][nN][gG]_[jJ][oO][iI][nN][tT][lL][yY]|[mM][fF][sS]|[mM][aA][rR][rR][iI][eE][dD]_[fF][iI][lL][iI][nN][gG]_[sS][eE][pP][aA][rR][aA][tT][eE][lL][yY]|[hH][oO][hH]|[hH][eE][aA][dD]_[oO][fF]_[hH][oO][uU][sS][eE][hH][oO][lL][dD]|[qQ][sS][sS]|[qQ][uU][aA][lL][iI][fF][yY][iI][nN][gG]_[sS][uU][rR][vV][iI][vV][iI][nN][gG]_[sS][pP][oO][uU][sS][eE])$", "examples": [ "single", "mfj", "married_filing_jointly", "mfs", "married_filing_separately", "hoh", "head_of_household", "qss", "qualifying_surviving_spouse" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "single", "x-relation": "The return's filing status: the brackets, the standard deduction, the thresholds.", "x-limits": "One of the nine strings, any case; null = absent. Anything else: 400 naming the field." }, "age": { "type": "integer", "minimum": 0, "maximum": 120, "description": "The age the filer reaches in 2026 (the age clock: the birth year is 2026 minus age). The §72(t) additional tax applies through the year the filer reaches 59 (with birthMonth, only to the part of the year before 59½); the §63(f) aged amount and the senior deduction from the year the filer reaches 65.", "x-whenAbsent": "(none: 400)", "x-relation": "The primary filer (the owner of iraDistributions).", "x-limits": "Whole number 0 to 120. Absent: 400 \"age is required\"." }, "spouseAge": { "type": [ "integer", "null" ], "minimum": 1, "maximum": 120, "description": "The spouse's age at the end of 2026, on a joint return: a spouse 65 or older adds the §63(f) married amount and their own senior deduction.", "x-whenAbsent": "(none: 400 on a joint return)", "x-relation": "Joint returns only.", "x-limits": "Whole number 1 to 120. Required when filingStatus is mfj; refused on any other status." }, "spouse_age": { "type": [ "integer", "null" ], "minimum": 1, "maximum": 120, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "(none: 400 on a joint return)", "x-relation": "Joint returns only.", "x-limits": "Whole number 1 to 120. Required when filingStatus is mfj; refused on any other status." }, "mfsLivedApart": { "type": [ "boolean", "null" ], "description": "true: a separate filer who lived apart from the spouse all year, so the Social Security test uses the single base amounts ($25,000 and $34,000) instead of $0 (Pub 915).", "x-whenAbsent": "false", "x-relation": "Separate returns only.", "x-limits": "true or false; null = absent. true on any other status: 400." }, "mfs_lived_apart": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "false", "x-relation": "Separate returns only.", "x-limits": "true or false; null = absent. true on any other status: 400." }, "iraDistributions": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Taxable distributions from traditional IRAs and employer plans (Form 1040 line 4b). The §72(t) additional tax applies to them by the filer's age.", "x-whenAbsent": "0", "x-relation": "Component: added to income once. Does not contain rothConversion.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "ira_distributions": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Component: added to income once. Does not contain rothConversion.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "rothConversion": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Amounts converted from a traditional account to a Roth IRA this year: ordinary income on line 4b, never charged the §72(t) additional tax.", "x-whenAbsent": "0", "x-relation": "Component: added to income once. Not part of iraDistributions.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "roth_conversion": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Component: added to income once. Not part of iraDistributions.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "pension": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Taxable pension and annuity income (Form 1040 line 5b), including Railroad Retirement Tier 2.", "x-whenAbsent": "0", "x-relation": "Component: added to income once.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "otherOrdinaryIncome": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Other ordinary income that is not net investment income (Form 1040 line 8). Not interest or dividends: the engine does not model those yet, and they would change the NIIT.", "x-whenAbsent": "0", "x-relation": "Component: added to income once.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "other_ordinary_income": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Component: added to income once.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "shortTermGains": { "type": [ "number", "null" ], "minimum": -100000000000, "maximum": 100000000000, "description": "The year's net short-term capital gain, or loss as a negative number (Schedule D line 7).", "x-whenAbsent": "0", "x-relation": "Component; netted against longTermGains.", "x-limits": "Finite, from -$100 billion to $100 billion; null = absent. Otherwise 400 naming the field." }, "short_term_gains": { "type": [ "number", "null" ], "minimum": -100000000000, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Component; netted against longTermGains.", "x-limits": "Finite, from -$100 billion to $100 billion; null = absent. Otherwise 400 naming the field." }, "longTermGains": { "type": [ "number", "null" ], "minimum": -100000000000, "maximum": 100000000000, "description": "The year's net long-term capital gain, or loss as a negative number (Schedule D line 15).", "x-whenAbsent": "0", "x-relation": "Component; netted against shortTermGains.", "x-limits": "Finite, from -$100 billion to $100 billion; null = absent. Otherwise 400 naming the field." }, "long_term_gains": { "type": [ "number", "null" ], "minimum": -100000000000, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Component; netted against shortTermGains.", "x-limits": "Finite, from -$100 billion to $100 billion; null = absent. Otherwise 400 naming the field." }, "socialSecurityGross": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Gross Social Security benefits received (with any Railroad Retirement Tier 1), Form 1040 line 6a. The engine computes the taxable part.", "x-whenAbsent": "0", "x-relation": "Gross benefits; the taxable part (line 6b) is computed, not sent.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "social_security_gross": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Gross benefits; the taxable part (line 6b) is computed, not sent.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "taxExemptInterest": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Tax-exempt interest (Form 1040 line 2a): not taxed, but counted in provisional income for Social Security.", "x-whenAbsent": "0", "x-relation": "Not added to AGI.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "tax_exempt_interest": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Not added to AGI.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "includeSources": { "type": [ "boolean", "null" ], "description": "false leaves rules.sources and rules.unsourced out of the response; the result is the same.", "x-whenAbsent": "true", "x-relation": "Not an engine input: shapes the response only.", "x-limits": "true or false; null = true. Anything else: 400." }, "include_sources": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "true", "x-relation": "Not an engine input: shapes the response only.", "x-limits": "true or false; null = true. Anything else: 400." }, "birthMonth": { "type": [ "integer", "null" ], "minimum": 1, "maximum": 12, "description": "The filer's birth month (1 to 12). With it, the §72(t) additional tax applies only to the share of the year before 59½ (the month of 59½ counts as before it), the Roth 59½ test uses the same share, and the split-interest QCD 70½ test is exact. Without it the whole-year rules apply: the additional tax through the year the filer reaches 59.", "x-whenAbsent": "(none: the whole-year rules)", "x-relation": "The age clock: age is the age reached in 2026, so the birth year is 2026 minus age.", "x-limits": "Whole number 1 to 12; null = absent." }, "birth_month": { "type": [ "integer", "null" ], "minimum": 1, "maximum": 12, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "(none: the whole-year rules)", "x-relation": "The age clock: age is the age reached in 2026, so the birth year is 2026 minus age.", "x-limits": "Whole number 1 to 12; null = absent." }, "blindCount": { "type": [ "integer", "null" ], "minimum": 0, "maximum": 2, "description": "How many people on the return are blind at the end of 2026 (§63(f)(2)): the filer, and on a joint return the spouse. Each adds the §63(f) amount to the standard deduction.", "x-whenAbsent": "0", "x-relation": "Joint returns only for 2.", "x-limits": "Whole number 0 to 2; 2 needs filingStatus mfj (400 otherwise)." }, "blind_count": { "type": [ "integer", "null" ], "minimum": 0, "maximum": 2, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Joint returns only for 2.", "x-limits": "Whole number 0 to 2; 2 needs filingStatus mfj (400 otherwise)." }, "saltIncomeOrSalesTax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "State and local income tax, or general sales tax instead (Schedule A line 5a).", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "salt_income_or_sales_tax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "saltRealEstateTax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "State and local real estate tax (Schedule A line 5b).", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "salt_real_estate_tax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "saltPersonalPropertyTax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "State and local personal property tax (Schedule A line 5c).", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "salt_personal_property_tax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "otherTaxes": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Other deductible taxes, such as foreign income tax (Schedule A line 6); not under the SALT cap.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "other_taxes": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "mortgageInterest": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Deductible home mortgage interest and points (Schedule A lines 8a to 8c), already limited to the qualified-residence debt limit.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "mortgage_interest": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "investmentInterest": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Deductible investment interest from Form 4952 (Schedule A line 9).", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "investment_interest": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "charityCash": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Cash gifts to public charities (§170(b)(1)(A) organizations), including any to donor-advised funds.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "charity_cash": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "charityCashDaf": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The part of charityCash given to a donor-advised fund or a supporting organization: deductible when itemizing, not for the non-itemizer deduction.", "x-whenAbsent": "0", "x-relation": "Part of charityCash; cannot exceed it (400).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "charity_cash_daf": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Part of charityCash; cannot exceed it (400).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "charityCapitalGainProperty": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Fair market value of long-term capital-gain property given to public charities (the 30% limit).", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "charity_capital_gain_property": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "medicalExpenses": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Unreimbursed medical and dental expenses (Schedule A line 1).", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "medical_expenses": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "otherItemized": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Other itemized deductions (Schedule A line 16), with no floor or cap.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "other_itemized": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Schedule A amount paid in 2026.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "itemizeMode": { "type": [ "string", "null" ], "pattern": "^(?:[aA][uU][tT][oO]|[iI][tT][eE][mM][iI][zZ][eE]|[sS][tT][aA][nN][dD][aA][rR][dD])$", "examples": [ "auto", "itemize", "standard" ], "description": "auto takes the larger of Schedule A (after §68) and the standard deduction plus the non-itemizer charitable deduction; itemize elects Schedule A even when smaller (Schedule A line 18); standard never itemizes.", "x-whenAbsent": "auto", "x-relation": "The §63(e) election.", "x-limits": "auto, itemize or standard, any case; null = absent." }, "itemize_mode": { "type": [ "string", "null" ], "pattern": "^(?:[aA][uU][tT][oO]|[iI][tT][eE][mM][iI][zZ][eE]|[sS][tT][aA][nN][dD][aA][rR][dD])$", "examples": [ "auto", "itemize", "standard" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "auto", "x-relation": "The §63(e) election.", "x-limits": "auto, itemize or standard, any case; null = absent." }, "mfsSpouseItemizes": { "type": [ "boolean", "null" ], "description": "On a separate return: the spouse itemizes, so this filer's standard deduction is zero and the return itemizes (§63(c)(6)(A)).", "x-whenAbsent": "false", "x-relation": "filingStatus mfs only (true on another status: 400).", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "mfs_spouse_itemizes": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "false", "x-relation": "filingStatus mfs only (true on another status: 400).", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "employerPlanDistribution": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The part of iraDistributions paid by a qualified employer plan (401(k), 403(b), governmental plan), not an IRA: the only dollars the separation-from-service exception covers.", "x-whenAbsent": "0", "x-relation": "Part of iraDistributions; cannot exceed it (400).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "employer_plan_distribution": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Part of iraDistributions; cannot exceed it (400).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "separationYearAge": { "type": [ "integer", "null" ], "minimum": 1, "maximum": 120, "description": "The age the filer reached in the year they left the employer that maintains the plan. At 55 or more (50 for a public safety employee) employerPlanDistribution is excepted from the §72(t) additional tax.", "x-whenAbsent": "(none: not separated)", "x-relation": "At most age (400 otherwise).", "x-limits": "Whole number 1 to 120; null = absent." }, "separation_year_age": { "type": [ "integer", "null" ], "minimum": 1, "maximum": 120, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "(none: not separated)", "x-relation": "At most age (400 otherwise).", "x-limits": "Whole number 1 to 120; null = absent." }, "publicSafetyEmployee": { "type": [ "boolean", "null" ], "description": "A qualified public safety employee (§72(t)(10)): the separation age is 50.", "x-whenAbsent": "false", "x-relation": "Read with separationYearAge.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "public_safety_employee": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "false", "x-relation": "Read with separationYearAge.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "seppDistribution": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The part of iraDistributions that is an installment of substantially equal periodic payments (§72(t)(2)(A)(iv)); its taxable part is excepted. The engine does not compute the payment schedule.", "x-whenAbsent": "0", "x-relation": "Part of iraDistributions; cannot exceed it (400).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "sepp_distribution": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Part of iraDistributions; cannot exceed it (400).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "disabled": { "type": [ "boolean", "null" ], "description": "The filer is disabled (§72(m)(7)): no §72(t) additional tax, and a Roth distribution can be qualified before 59½.", "x-whenAbsent": "false", "x-relation": "The primary filer.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "iraBasis": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Total nondeductible basis in traditional IRAs (Form 8606 line 5: prior-year basis plus this year's nondeductible contributions).", "x-whenAbsent": "0", "x-relation": "Read with iraYearEndValue.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "ira_basis": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Read with iraYearEndValue.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "iraYearEndValue": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The value of all traditional, SEP and SIMPLE IRAs on December 31, 2026, plus outstanding rollovers (Form 8606 line 6).", "x-whenAbsent": "0", "x-relation": "Read with iraBasis.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "ira_year_end_value": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Read with iraBasis.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "rothDistribution": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Gross Roth IRA distributions in 2026.", "x-whenAbsent": "0", "x-relation": "Not part of iraDistributions.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "roth_distribution": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Not part of iraDistributions.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "rothContributions": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Regular Roth contributions still in the Roth at the start of 2026 (distributed first).", "x-whenAbsent": "0", "x-relation": "Read with rothDistribution.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "roth_contributions": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Read with rothDistribution.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "rothFirstContributionYear": { "type": [ "integer", "null" ], "minimum": 1998, "maximum": 2026, "description": "The first tax year a contribution was made to any Roth IRA for the filer (the qualified-distribution 5-year clock).", "x-whenAbsent": "(none: the 5-year clock is taken as not met)", "x-relation": "Read with rothDistribution.", "x-limits": "Whole number 1998 to 2026; null = absent." }, "roth_first_contribution_year": { "type": [ "integer", "null" ], "minimum": 1998, "maximum": 2026, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "(none: the 5-year clock is taken as not met)", "x-relation": "Read with rothDistribution.", "x-limits": "Whole number 1998 to 2026; null = absent." }, "rothConversions": { "type": [ "array", "null" ], "maxItems": 16, "items": { "type": "object", "properties": { "year": { "type": "integer", "minimum": 1998, "maximum": 2026 }, "taxable": { "type": "number", "minimum": 0, "maximum": 100000000000 }, "nontaxable": { "type": "number", "minimum": 0, "maximum": 100000000000 } }, "required": [ "year", "taxable" ], "additionalProperties": false }, "description": "The conversions still in the Roth at the start of 2026: [{year, taxable, nontaxable}], any order. They come out oldest first, each one's taxable part first; a taxable part taken within 5 years of its conversion carries the §72(t) additional tax under 59½.", "x-whenAbsent": "[] (none)", "x-relation": "Read with rothDistribution.", "x-limits": "At most 16 objects: year a whole number 1998 to 2026, taxable and nontaxable dollars 0 to $100 billion (nontaxable may be left out); no other key. Otherwise 400." }, "roth_conversions": { "type": [ "array", "null" ], "maxItems": 16, "items": { "type": "object", "properties": { "year": { "type": "integer", "minimum": 1998, "maximum": 2026 }, "taxable": { "type": "number", "minimum": 0, "maximum": 100000000000 }, "nontaxable": { "type": "number", "minimum": 0, "maximum": 100000000000 } }, "required": [ "year", "taxable" ], "additionalProperties": false }, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "[] (none)", "x-relation": "Read with rothDistribution.", "x-limits": "At most 16 objects: year a whole number 1998 to 2026, taxable and nontaxable dollars 0 to $100 billion (nontaxable may be left out); no other key. Otherwise 400." }, "iraBalancePriorYearEnd": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The traditional IRA balance on December 31, 2025: with it the response carries the 2026 required minimum distribution (schedules.rmd).", "x-whenAbsent": "0", "x-relation": "The account owner is the filer (age, birth year 2026 minus age).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "ira_balance_prior_year_end": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "The account owner is the filer (age, birth year 2026 minus age).", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "spouseSoleBeneficiary": { "type": [ "boolean", "null" ], "description": "The spouse is the sole beneficiary all year: when more than 10 years younger, the RMD uses the Joint and Last Survivor Table.", "x-whenAbsent": "false", "x-relation": "Needs iraBalancePriorYearEnd; the spouse's age is spouseAge on a joint return, else beneficiarySpouseAge. Refused for a qualifying surviving spouse.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "spouse_sole_beneficiary": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "false", "x-relation": "Needs iraBalancePriorYearEnd; the spouse's age is spouseAge on a joint return, else beneficiarySpouseAge. Refused for a qualifying surviving spouse.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "beneficiarySpouseAge": { "type": [ "integer", "null" ], "minimum": 0, "maximum": 120, "description": "The spouse's age reached in 2026 when the spouse is not on the return (a separate return).", "x-whenAbsent": "(none)", "x-relation": "Needs spouseSoleBeneficiary true; refused on a joint return (spouseAge is used).", "x-limits": "Whole number 0 to 120; null = absent." }, "beneficiary_spouse_age": { "type": [ "integer", "null" ], "minimum": 0, "maximum": 120, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "(none)", "x-relation": "Needs spouseSoleBeneficiary true; refused on a joint return (spouseAge is used).", "x-limits": "Whole number 0 to 120; null = absent." }, "rmdShortfall": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The part of a required minimum distribution not taken: the §4974 excise, 25%.", "x-whenAbsent": "0", "x-relation": "Form 5329 Part IX.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "rmd_shortfall": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Form 5329 Part IX.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "rmdShortfallCorrected": { "type": [ "boolean", "null" ], "description": "The shortfall was distributed within the correction window: the excise is 10%.", "x-whenAbsent": "false", "x-relation": "Read with rmdShortfall.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "rmd_shortfall_corrected": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "false", "x-relation": "Read with rmdShortfall.", "x-limits": "true or false; null = absent (false). Anything else: 400." }, "priorYearTax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The tax on the 2025 return (Form 2210 line 8). With it the response carries Form 2210 (schedules.form2210) on this return's tax.", "x-whenAbsent": "0", "x-relation": "Turns on Form 2210.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "prior_year_tax": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Turns on Form 2210.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "priorYearAgi": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The 2025 AGI: above $150,000 ($75,000 on a separate return) the prior-year safe harbor is 110%.", "x-whenAbsent": "0", "x-relation": "Needs priorYearTax.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "prior_year_agi": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "0", "x-relation": "Needs priorYearTax.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "priorYearFullYearReturn": { "type": [ "boolean", "null" ], "description": "false when 2025 was not a full 12-month year with a return filed: the prior-year safe harbor and the no-liability rule do not apply.", "x-whenAbsent": "true", "x-relation": "Needs priorYearTax.", "x-limits": "true or false; null = absent (true). Anything else: 400." }, "prior_year_full_year_return": { "type": [ "boolean", "null" ], "description": "The same field under its snake_case spelling.", "x-whenAbsent": "true", "x-relation": "Needs priorYearTax.", "x-limits": "true or false; null = absent (true). Anything else: 400." }, "withholding": { "type": [ "number", "null" ], "minimum": 0, "maximum": 100000000000, "description": "Income tax withheld in 2026: counted as paid in four equal parts on the due dates.", "x-whenAbsent": "0", "x-relation": "Needs priorYearTax.", "x-limits": "Finite, from 0 to $100 billion; null = absent. Otherwise 400 naming the field." }, "estimatedPayments": { "type": [ "array", "null" ], "maxItems": 4, "items": { "type": "number", "minimum": 0, "maximum": 100000000000 }, "description": "The four 2026 estimated tax payments, in installment order.", "x-whenAbsent": "[0, 0, 0, 0]", "x-relation": "Needs priorYearTax.", "x-limits": "Up to 4 amounts, dollars 0 to $100 billion. Otherwise 400." }, "estimated_payments": { "type": [ "array", "null" ], "maxItems": 4, "items": { "type": "number", "minimum": 0, "maximum": 100000000000 }, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "[0, 0, 0, 0]", "x-relation": "Needs priorYearTax.", "x-limits": "Up to 4 amounts, dollars 0 to $100 billion. Otherwise 400." }, "estimatedPaymentDates": { "type": [ "array", "null" ], "maxItems": 4, "items": { "type": [ "string", "null" ], "pattern": "^202[678]-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])$" }, "description": "The date each estimated payment was made; null for one paid on its due date. Accrual stops at the earlier of the payment date and April 15, 2027.", "x-whenAbsent": "each installment's due date", "x-relation": "Needs priorYearTax.", "x-limits": "Up to 4 dates YYYY-MM-DD from 2026-01-01 to 2028-12-31, or null. Otherwise 400." }, "estimated_payment_dates": { "type": [ "array", "null" ], "maxItems": 4, "items": { "type": [ "string", "null" ], "pattern": "^202[678]-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])$" }, "description": "The same field under its snake_case spelling.", "x-whenAbsent": "each installment's due date", "x-relation": "Needs priorYearTax.", "x-limits": "Up to 4 dates YYYY-MM-DD from 2026-01-01 to 2028-12-31, or null. Otherwise 400." } }, "required": [ "age" ], "additionalProperties": false, "x-errors": [ { "message": "Invalid JSON body", "when": "The body is not JSON (or is empty)." }, { "message": "The request body must be a JSON object", "when": "The body is JSON but not an object." }, { "message": "{1} is not a field of the federal tax API: the engine models only the fields listed at https://quantcalc.app/docs/federal-tax/api/ (income it does not model must not be sent as if it were counted)", "when": "A key that is not a request field. {1} = the key, as sent." }, { "message": "{1} is given more than once (as two spellings or two cases of the key)", "when": "Two keys name the same field (camelCase and snake_case, or two cases)." }, { "message": "{1} must be a string, one of: {2}", "when": "filingStatus is not a string." }, { "message": "{1} \"{2}\" is not recognised — use one of: {3}", "when": "filingStatus is not one of the accepted values." }, { "message": "{1} must be a number (annual dollars)", "when": "An amount is not a number." }, { "message": "{1} must be a whole number between {2} and {3}", "when": "age or spouseAge is not a whole number in range." }, { "message": "{1} must be true or false", "when": "mfsLivedApart or includeSources is not a boolean." }, { "message": "{1} is required ({2})", "when": "A required field is absent or null. Only age is required: {2} says why (the filer's age at the end of the year decides the §72(t) additional tax, the §63(f) aged amount and the senior deduction)." }, { "message": "{1} must be a finite number", "when": "An amount is not finite (a number too large for a double)." }, { "message": "{1} cannot be negative", "when": "An amount other than the gains is below 0." }, { "message": "{1} is below the engine's range (-$100 billion)", "when": "A gain is below -$100 billion." }, { "message": "{1} is larger than the engine accepts ($100 billion)", "when": "An amount is above $100 billion." }, { "message": "spouseAge applies only to filingStatus mfj (the spouse's §63(f) aged amount and senior deduction are claimed on a joint return)", "when": "spouseAge on a status other than mfj." }, { "message": "spouseAge is required when filingStatus is mfj (the spouse's age at the end of the year decides their §63(f) aged amount and senior deduction)", "when": "A joint return without spouseAge." }, { "message": "mfsLivedApart applies only to filingStatus mfs (Pub 915: a separate filer who lived apart from their spouse all year)", "when": "mfsLivedApart: true on a status other than mfs." }, { "message": "{1} must be an array of at most {2} objects {year, taxable, nontaxable}: year a whole number {3} to {4}, the amounts dollars 0 or more (nontaxable may be left out)", "when": "rothConversions is not a list of conversions." }, { "message": "{1} must be an array of up to 4 amounts (dollars, 0 or more), one per installment", "when": "estimatedPayments is not a list of up to 4 amounts." }, { "message": "{1} must be an array of up to 4 dates \"YYYY-MM-DD\" from 2026-01-01 to 2028-12-31 (null = paid on the installment's due date)", "when": "estimatedPaymentDates holds something that is not such a date." }, { "message": "blindCount 2 needs filingStatus mfj (a spouse's §63(f) amount for blindness is claimed on a joint return)", "when": "blindCount 2 on another status." }, { "message": "mfsSpouseItemizes applies only to filingStatus mfs (§63(c)(6)(A): a separate filer whose spouse itemizes has no standard deduction)", "when": "mfsSpouseItemizes true on another status." }, { "message": "{1} is part of iraDistributions and cannot exceed it", "when": "employerPlanDistribution or seppDistribution above iraDistributions." }, { "message": "charityCashDaf is part of charityCash and cannot exceed it", "when": "charityCashDaf above charityCash." }, { "message": "separationYearAge cannot exceed age (it is the age reached in the year the filer left the employer)", "when": "separationYearAge above age." }, { "message": "beneficiarySpouseAge needs spouseSoleBeneficiary true (it only picks the RMD table)", "when": "beneficiarySpouseAge without spouseSoleBeneficiary." }, { "message": "spouseSoleBeneficiary needs iraBalancePriorYearEnd (it picks the table the RMD is figured with)", "when": "spouseSoleBeneficiary without a balance." }, { "message": "spouseSoleBeneficiary cannot apply to a qualifying surviving spouse (there is no spouse)", "when": "spouseSoleBeneficiary with filingStatus qss." }, { "message": "beneficiarySpouseAge is for a spouse who is not on the return: on a joint return the RMD reads spouseAge", "when": "beneficiarySpouseAge on a joint return." }, { "message": "spouseSoleBeneficiary needs beneficiarySpouseAge (the spouse's age reached in 2026) unless filingStatus is mfj", "when": "spouseSoleBeneficiary on a non-joint return without beneficiarySpouseAge." }, { "message": "{1} needs priorYearTax (Form 2210 runs only with last year's tax)", "when": "A Form 2210 field without priorYearTax." } ] }, "response": { "type": "object", "properties": { "engineVersion": { "type": "string", "description": "The federal engine version (FEDERAL_TAX_ENGINE_VERSION)." }, "taxYear": { "type": "integer", "description": "2026." }, "filingStatus": { "type": "string", "description": "single, mfj, mfs, hoh or qss: the status the return was computed on." }, "inputs": { "type": "object", "description": "Every field that was sent, under its camelCase name.", "properties": {} }, "result": { "type": "object", "description": "The year's return.", "properties": { "shortTermGain": { "type": "number", "description": "Short-term gain after netting, at least 0 (taxed as ordinary income)." }, "longTermGain": { "type": "number", "description": "Long-term gain after netting, at least 0." }, "socialSecurityTaxable": { "type": "number", "description": "The taxable part of the benefits (line 6b)." }, "grossOrdinaryIncome": { "type": "number", "description": "Ordinary income: IRA distributions, conversions, pension, other income, taxable Social Security and the short-term gain." }, "agi": { "type": "number", "description": "Adjusted gross income (line 11a); also the NIIT's and the senior deduction's MAGI." }, "magiIrmaa": { "type": "number", "description": "AGI plus tax-exempt interest: the income the engine's Medicare IRMAA tiers read." }, "standardDeduction": { "type": "number", "description": "The standard deduction with the §63(f) aged amounts (line 12e)." }, "seniorDeduction": { "type": "number", "description": "The senior deduction after its phase-out (line 13b)." }, "taxableOrdinaryIncome": { "type": "number", "description": "The ordinary part of taxable income." }, "unusedDeduction": { "type": "number", "description": "Deductions left after ordinary income, which reduce the long-term gain in the worksheet." }, "taxableLongTermGain": { "type": "number", "description": "The long-term gain in taxable income (the worksheet's base)." }, "ordinaryTax": { "type": "number", "description": "Bracket tax on the ordinary part." }, "capitalGainsTax": { "type": "number", "description": "Worksheet tax on the long-term gain plus the NIIT." }, "niit": { "type": "number", "description": "The net investment income tax (Schedule 2 line 12)." }, "incomeTax": { "type": "number", "description": "ordinaryTax + capitalGainsTax: income tax with the NIIT, without the §72(t) additional tax." }, "incomeTaxExcludingNiit": { "type": "number", "description": "incomeTax less the NIIT: line 16 (and, with no credits modelled, line 22)." }, "earlyWithdrawalTax": { "type": "number", "description": "The §72(t) additional tax (Schedule 2 line 8)." }, "totalTax": { "type": "number", "description": "incomeTax + earlyWithdrawalTax: line 24. With extended fields it also carries the missed-RMD excise (Form 5329 line 55)." } } }, "lines": { "type": "array", "description": "One entry per Form 1040 or schedule line the composition fills, in form order.", "items": { "type": "object", "properties": { "line": { "type": "string", "description": "The line id: 1040., 1040sd. (Schedule D), 1040s1a. (Schedule 1-A), 1040s2. (Schedule 2); TY2025 form numbering." }, "form": { "type": "string", "description": "The form or schedule." }, "lineNumber": { "type": "string", "description": "The line number on it." }, "label": { "type": "string", "description": "The line's name." }, "rule": { "type": "string", "description": "The calculation step that produced the value (a section of the calculation-order page)." }, "value": { "type": "number", "description": "The amount." }, "docs": { "type": "string", "description": "The step's documentation." } } } }, "rules": { "type": "object", "description": "What the figure rests on.", "properties": { "docs": { "type": "string", "description": "The engine documentation." }, "sources": { "type": "object", "description": "Per calculation step on the return: its official sources (absent with includeSources: false).", "additionalProperties": { "type": "array", "items": { "type": "object", "properties": { "rule": { "type": "string", "description": "The provenance record (research/data/federal-tax-provenance.json)." }, "url": { "type": "string", "description": "The source." }, "title": { "type": "string", "description": "Its title." }, "publisher": { "type": "string", "description": "Its publisher." }, "kind": { "type": "string", "description": "statute, guidance, instructions, agency_page, ..." }, "official": { "type": "boolean", "description": "Published by the body that sets the rule, or the text of the law." }, "quote": { "type": "string", "description": "The first passage checked on the source." }, "checked": { "type": "string", "description": "The date the quote was last found on the source." } } } } }, "unsourced": { "type": "array", "description": "Steps on the return with no official source, with the reason (absent with includeSources: false).", "items": { "type": "object", "properties": { "rule": { "type": "string", "description": "The step." }, "reason": { "type": "string", "description": "Why." } } } }, "notModeled": { "type": "array", "description": "What the engine does not compute.", "items": { "type": "string" } } } }, "schedules": { "type": "object", "description": "On a request with any extended field (or filingStatus qss): the forms behind the return.", "properties": { "scheduleA": { "type": "object", "description": "Schedule A, the §68 limitation, the standard deduction and the non-itemizer charitable deduction.", "properties": { "itemizes": { "type": "boolean", "description": "true when line 12e carries Schedule A." }, "deduction": { "type": "number", "description": "Form 1040 line 12e as filed (equals result.standardDeduction)." }, "standardDeduction": { "type": "number", "description": "The standard deduction available, with the §63(f) aged and blind amounts (0 under §63(c)(6)(A))." }, "blindAddition": { "type": "number", "description": "The §63(f)(2) amount for blindness included in it." }, "itemizedBeforeSection68": { "type": "number", "description": "Schedule A lines 4 to 16 before §68." }, "section68Reduction": { "type": "number", "description": "The 2/37 limitation of §68." }, "itemized": { "type": "number", "description": "Schedule A line 17 after §68: the figure an itemized-conformity state reads." }, "medicalDeducted": { "type": "number", "description": "Line 4." }, "saltPaid": { "type": "number", "description": "Line 5d." }, "saltCap": { "type": "number", "description": "The SALT cap after the phase-down (half on a separate return)." }, "saltDeducted": { "type": "number", "description": "Line 5e." }, "interestDeducted": { "type": "number", "description": "Line 10." }, "charityFloor": { "type": "number", "description": "0.5% of AGI (2026)." }, "charityDeducted": { "type": "number", "description": "Line 14 after the percentage limits and the floor." }, "nonitemizerCharity": { "type": "number", "description": "The §170(p) deduction (0 when itemizing)." } } }, "form8606": { "type": "object", "description": "IRA basis and Roth distributions.", "properties": { "basisRatio": { "type": "number", "description": "Line 10 (0 without basis)." }, "nontaxableConversion": { "type": "number", "description": "Line 11." }, "nontaxableTotal": { "type": "number", "description": "Line 13." }, "basisRemaining": { "type": "number", "description": "Line 14." }, "rothQualified": { "type": "boolean", "description": "true when the Roth distribution is qualified." }, "rothTaxableEarnings": { "type": "number", "description": "Line 25c: taxable Roth earnings." }, "rothConversionsWithinFiveYears": { "type": "number", "description": "Converted amounts taken within 5 years of their conversion (subject to the additional tax, not taxable)." }, "rothContributionsRemaining": { "type": "number", "description": "Regular contributions left in the Roth." } } }, "form5329": { "type": "object", "description": "The additional taxes on retirement accounts.", "properties": { "earlyDistributions": { "type": "number", "description": "Line 1." }, "exceptions": { "type": "number", "description": "Line 2." }, "missedRmdExcise": { "type": "number", "description": "Line 55: the §4974 excise (in result.totalTax)." } } }, "rmd": { "type": "object", "description": "With iraBalancePriorYearEnd: the 2026 required minimum distribution.", "properties": { "startAge": { "type": "integer", "description": "The SECURE 2.0 applicable age for the birth year." }, "divisor": { "type": "number", "description": "The divisor (0 before the start age)." }, "jointLifeTable": { "type": "boolean", "description": "true when the Joint and Last Survivor Table applies." }, "required": { "type": "number", "description": "The required minimum distribution." } } }, "form2210": { "type": "object", "description": "With priorYearTax: Form 2210 (regular method) on this return's tax.", "properties": { "tax": { "type": "number", "description": "The tax Form 2210 uses: income tax plus the additional tax on distributions." }, "requiredAnnualPayment": { "type": "number", "description": "Line 9." }, "requiredInstallment": { "type": "number", "description": "Line 10, each installment." }, "priorYearSafeHarbor": { "type": "boolean", "description": "true when the prior-year harbor sets the requirement." }, "underThousandDollars": { "type": "boolean", "description": "true when the tax less withholding is under the §6654(e)(1) threshold: no penalty." }, "noPriorYearLiability": { "type": "boolean", "description": "true when last year's full-year return showed no tax: no penalty." }, "underpayment": { "type": "array", "description": "Line 17 per installment.", "items": { "type": "number" } }, "penaltyByInstallment": { "type": "array", "description": "The penalty attributable to each installment.", "items": { "type": "number" } }, "totalUnderpayment": { "type": "number", "description": "The sum of line 17." }, "penalty": { "type": "number", "description": "Line 19." }, "usesUnannouncedRate": { "type": "boolean", "description": "true when some accrual falls in a quarter whose rate is carried forward, not announced." } } } } } } }, "error": { "type": "object", "properties": { "error": { "type": "string", "description": "One of the messages under #/$defs/request/x-errors, with the parts taken from the request filled in." } }, "required": [ "error" ] } } }