About Self Employed Math

Self Employed Math is an independent publisher of free calculators for freelancers, 1099 contractors, gig workers and hourly earners in the United States. We aren't a tax firm, a CPA practice, or affiliated with the IRS.

Methodology

• Every number (rates, brackets, limits) comes from a primary source such as IRS.gov or SSA.gov, and each calculator links to it.
• Formulas are shown in plain English on every page, with a worked example you can check by hand.
• Every release is checked by automated tests against hand-calculated cases built from IRS and SSA tables and rates.
• Each page shows a "last reviewed" date. We check for IRS changes regularly and update when rules change, such as the mid-2026 mileage rate change.

Limits

Our tools give estimates for federal taxes only and leave out many credits, state taxes and special situations. They are not tax advice.

Last updated October 29, 2026.