Last updated: October 21, 2026.
Rules come from the IRS, in writing
Every rule used by a calculator on this site is kept in a written rules register with its source. The register prefers, in order: the Schedule 1-A form and instructions themselves, IRS fact sheets and notices (FS-2026-13 for overtime, FS-2026-04 for Schedule 1-A), the final Treasury regulations (T.D. 10044 for tips), and IRS news releases. Two points began as professional summaries rather than our own read of the primary text (the tips regulation edge cases and the 1099 threshold wording); both were re-read on the primary text before publication, and every figure on the site now traces to a primary source read directly.
The occupation list is the IRS list
The tipped occupations dataset behind the checker and the list page was extracted from the IRS page "Occupations that customarily and regularly received tips on or before Dec. 31, 2024" on October 17, 2026: 71 occupations, 8 categories, with Treasury Tipped Occupation Codes. The extraction date is shown on the list page.
Calculators are tested against hand-worked examples
Each engine ships with a test file of examples worked by hand from the IRS documents, never produced by the engine itself. The suite includes the traps this topic is known for: a $9,000 overtime total that yields only a $3,000 deduction, a car loan phase-out that rounds up where the others round down, a 1099-K amount over $20,000 that is not reportable because the transaction count is under 200, and a W-2 code TT figure that cannot be topped up from paystubs after 2025. Tests run on every build.
Estimates, not advice
Results are estimates from the information entered. The site does not know your full tax position and is not tax advice. Where a figure depends on something personal, like your marginal rate, the site asks you for it rather than assuming.
Corrections
When a rule changes or an error is found, the page is corrected and its updated date is changed. The Internal Revenue Code sections behind these deductions are 224 (tips) and 225 (overtime), with qualified car loan interest under section 163(h)(4), all claimed on Schedule 1-A (Form 1040) for tax years 2025 to 2028.