Free · No API key · CORS enabled
Free US Tax Data API
The same verified tax data that powers every DollarCalcs calculator, as clean JSON. Sourced from the IRS and state statutes (compiled with the Tax Foundation's published tables), updated every January and July.
Federal brackets, standard deductions, Social Security wage base and Medicare rates for 2026.
Income tax structure for all 50 states + D.C.: type (none/flat/graduated), single-filer brackets, deductions, top rates.
State, average local, max local and combined sales tax rates for all states, as of July 2026.
Usage
No authentication, no rate limits for reasonable use, CORS open, responses cached for 24 hours. Example:
fetch("https://dollarcalcs.com/api/v1/state-income-tax")
.then(r => r.json())
.then(d => console.log(d.states.find(s => s.abbr === "NY")));License
Free for any use, commercial included. We ask for attribution with a link to dollarcalcs.com wherever the data is displayed. The data is provided as-is; verify against official sources before relying on it for filing or compliance. If you build something with it, tell us — we link to good projects from this page.
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