The math behind your health coverage decisions

Free, plain-English calculators for the health-insurance choices that actually cost money — subsidies, COBRA, deductions, Medicare surcharges. Every number is cited to a primary government source, and everything runs in your browser. No signup, no email, no data leaves your device.

Estimate my 2026 ACA subsidy →

Why CoverageMath?

Most health-insurance "calculators" exist to capture your phone number and sell it to an agent. Ours don't. There's no signup, no lead form, and no data leaves your browser. We build genuinely useful decision tools and show our work — the formulas, the data tables, and the primary sources behind every result — so you can check the math instead of trusting a black box.

Guides that explain the decisions

Numbers only help if you understand them. Our guides walk through the questions behind each calculator in plain English — every one cited to primary sources and kept current for 2026. Start with how ACA subsidies work, the 400% subsidy cliff, is COBRA worth it?, or Medicare IRMAA explained.

Built on public, citable data

Subsidy rules come from the IRS and HHS. Poverty guidelines come from ASPE. Medicare surcharges come from CMS and the Social Security Administration. Every year-dependent number on this site lives in an open data file with its source link and the date we last verified it — see our methodology.

This is reference information, not advice

CoverageMath provides estimates for education and planning only. It is not insurance, tax, legal, or financial advice. Final amounts are set by the Marketplace, the IRS, or the Social Security Administration. See our full disclaimer.