Datasets
State Retirement Tax Data 2026
Downloadable CSV/JSON dataset of per-state 2026 retirement-tax policy facts — top marginal rate, standard deduction, Social Security taxability, qualified-retirement-income exemptions, and Roth-conversion treatment for all 51 U.S. jurisdictions, generated directly from QuantCalc's frozen state-tax engine.
RMD Table 2026
Downloadable CSV/JSON dataset of the 2026 IRS Uniform Lifetime Table III used to calculate Required Minimum Distributions (RMDs) — distribution period factor and RMD percentage of balance for every age 72-120, plus the SECURE 2.0 RMD start-age table by birth year, generated directly from QuantCalc's canonical tax-constants mirror.
IRMAA Brackets 2026
Downloadable CSV/JSON dataset of the 2026 Medicare IRMAA brackets — per-tier MAGI thresholds (single and married filing jointly) with monthly and annual Part B and Part D surcharges, generated directly from QuantCalc's canonical tax-constants mirror.
Machine-readable index
Every dataset above, listed in one file (URL, title, version, last-updated date) so you don't have to scrape this page to find them.
Methodology
About these datasets: Every figure on every dataset page linked above is generated directly from QuantCalc's production tax engine or its canonical client-side tax-constants mirror — not hand-transcribed into HTML from a statute, IRS table, or CMS notice. Each dataset's own page documents its specific source function and scope in its Methodology section.
Consistency: The C engine and its JavaScript port are checked against each other by an exhaustive JS↔C parity test suite, so a dataset page, the interactive calculator, and the backend all report the same figures.
This index: Generated by scripts/gen_data_hub.mjs, which reads each dataset's own index.html head (title, description, canonical URL) and JSON envelope (version, generated date) rather than duplicating any tax figure. Re-running it against the same dataset pages reproduces byte-identical output.
Not tax advice: These are reference datasets for research and planning purposes, not a substitute for professional tax advice.
Turn this data into a plan
These datasets show the rules. The Roth Conversion Planner applies them to your own numbers — state tax, RMDs, and IRMAA cliffs included — to build a year-by-year conversion schedule.
Plan your Roth conversions →Looking for the research behind these numbers instead of the raw data? See the Research index.