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How we calculate

Every number on this site is computed, not copied. The inputs come from the published sources listed on each page, and the arithmetic is the same code that runs in your browser, in the pre-rendered tables, and in this project's tests — so the three cannot disagree.

What varies, and why it earns a page

States differ on THREE independent axes here: whether Social Security is taxed, whether pension income is exempt (often partially, often age-gated), and whether 401(k)/IRA withdrawals are taxed. That is a genuine 3-dimensional matrix, not one number swapped 50 times.

Structural classifications used here

Why some states share a page

6 pages cover this topic, with 44 states folded into the page that gives the identical answer. A jurisdiction earns its own URL only when its rules or numbers change the answer. Where two would produce the same page, they are covered together and the spare URL redirects into it. Publishing near-identical pages is worse for the reader and is a search-quality violation, so this site is built so it cannot happen: the build compares every page against its siblings on two independent similarity metrics and fails if any pair converges.

Limitations, stated plainly

These are estimates for general information, not advice. Local jurisdictions add rules a state-level model cannot capture, and statutes change. Verify with the relevant agency before acting on a number.

Last reviewed 2026-08-26.