About Ballpark Tax
Ballpark Tax publishes free calculators and plain-English guides for people in the United States who work for themselves.
Where the numbers come from
Every statutory figure — tax brackets, the standard deduction, the Social Security wage base, QBI thresholds — is taken from the IRS revenue procedure for that tax year, or from the Social Security Administration where applicable. The figures live in a single versioned file in the codebase with its sources cited in comments, so a reader can see exactly which year's rules a calculator is applying.
How the calculations are checked
The calculation engine is covered by an automated test suite with cases worked by hand, including the edge cases that most calculators get wrong: the Social Security wage base cap, W-2 wages consuming part of that cap, the Additional Medicare Tax being excluded from the deductible half of self-employment tax, and the QBI phase-out for service businesses.
What these tools will not do
- They do not cover state or local tax.
- They do not model the W-2 wage and property limits that apply to the QBI deduction at higher incomes. Where those limits would bite, the calculator says so rather than producing a confident wrong answer.
- They are not a substitute for a tax professional, and they do not file anything.
Editorial review
Articles covering tax rules are reviewed by a credentialed US tax professional before publication, and the reviewer's name and credential appear on the article. Where an article carries no reviewer byline, it has not yet been reviewed.
How this site makes money
Advertising, and affiliate commissions on software we link to. Advertising never influences which calculators get built or what the guides say, and the calculators carry no ads inside the tool itself.
Who writes this
Muhammad Aftab — Software engineer, founder of Ballpark Tax.
Built these calculators because the free ones were either wrong or refused to show their working. Not a tax professional: every figure here is taken from IRS publications and the calculations are covered by unit tests, but none of it is advice about your situation.
Corrections
If a figure here is wrong, it matters. Email [email protected] and it gets fixed, with the change noted on the page.