About Breakeven

Why this exists

Most people find out whether they over-withheld or under-withheld their federal income tax exactly once a year, in April, after it is too late to do anything about it. Breakeven is a simple calculator that answers that question in any month, from the paystubs already in your pocket — so you can adjust your W-4 before April instead of after.

Mission

Give an honest, arithmetic answer to one question — will you owe or get a refund in 2026? — and then, if the projection is off, show you the smallest W-4 change that brings it back to zero. That is the whole product. Breakeven is not a tax preparer, a filing service, or a refund estimator that upsells anything else.

How it works (in one sentence)

You enter your year-to-date paychecks and your current W-4 settings. Breakeven applies the 2026 IRS withholding tables and tax brackets, projects your end-of-year liability against your end-of-year withholding, shows you the gap, and — if you want — fills out a new W-4 PDF with a recommended Step 4(c) extra withholding amount that would have closed the gap. The full accounting is in the Methodology.

Privacy stance

Breakeven runs entirely in your browser. There is no server to send your paychecks to, no account to create, and no database on any side of the wire that holds your data. Closing the tab clears everything you entered. Your name and Social Security number, if you use the W-4 PDF generator, live in memory for the seconds it takes to stamp the PDF and are discarded when the dialog closes. The full disclosure, including how third-party ads are sandboxed, is in the Privacy policy.

Maintainer

Breakeven is a personal project maintained by a software engineer who got tired of a surprise April tax bill. The engine's math is cited against IRS publications so anyone can check it — see Methodology for the full source list.

What Breakeven is not

• Not tax advice. It is arithmetic from published IRS tables. Always verify material decisions with the IRS Tax Withholding Estimator or a qualified professional.
• Not a tax filer. Breakeven does not file returns or interact with the IRS. The filled W-4 PDF is yours to hand to your employer.
• Not a state tax calculator. Federal income tax only in Phase 1.
• Not data collection. Breakeven has no accounts, no analytics on your entries, and no place to store them.

Contact

Breakeven is a personal project, not a company. For bugs or corrections to the tax math, open an issue against the code repository. For anything time-sensitive that affects your actual tax return, talk to a qualified tax professional first.