What Calceva is
Calceva works out what a paycheck leaves you in any US state, using the figures the tax agencies publish themselves. Nothing here is bought from a data feed or copied from another calculator. Every rate we apply traces back to an IRS or state revenue document, and every state calculator page names the document and the date it was read.
Why it exists
Run the biggest paycheck calculators against the official 2026 tables and the same faults keep surfacing. Employee-paid programs go missing entirely: Massachusetts paid family leave, Colorado FAMLI, Paid Leave Oregon. Last year's rates stay in production months into the new year. And a reader has no way to check any of it, because the sources are never shown.
These are not rounding quibbles. A Massachusetts worker on $60,000 has up to about $276 a year withheld for PFML; a calculator that drops that line is wrong by a car insurance premium. We built this to close that gap and to show our work while doing it.
How the work is done
Federal brackets come from the IRS revenue procedure. State rates come from each state's revenue department, program rates from the agency that runs the program. Every state calculator page carries its paper trail, stamped with a date — all fifty-one of them.
Nothing publishes until the engine reproduces every hand-worked reference paycheck to the cent. One failure stops the release. There is no override.
We also test against other public calculators and against the agencies' own worked examples, and where we disagree with someone the divergence goes into the correction registry with its date and its source. That includes the times the mistake was ours. Rates go stale on their own schedule, so each page carries the date its figures were read, an automated watch re-reads the source documents, and the changelog says what moved.
What Calceva is not
We are not a tax preparer, an accounting firm, or an advisory service. These calculators produce estimates for planning; your real bill is settled by your tax return. For decisions about withholding or filing, talk to a qualified professional or to your tax agency. The terms of use say so in plainer legal language.
Corrections
If a rate here looks wrong, tell us, ideally with the document that says otherwise. Errors we can trace get fixed and published in the registry rather than quietly patched. The contact page reaches the data desk.