1099 Tax Calculator

How it is calculated

The tool first finds net earnings: net = income − expenses (never below zero). Self-employment tax is then charged on 92.35% of that net: SE tax = min(base, wage base) × 12.4% + base × 2.9%, where base = net × 0.9235. The 12.4% Social Security part stops at the current year's wage base (2026: 184,500; from 1 January 2027: 192,300; the result shows which one was used), while the 2.9% Medicare part applies to the whole base. Income tax is estimated as (net − SE tax ÷ 2) × bracket %, i.e. half of the SE tax is deducted first. Above $200,000 of SE earnings (the single-filer threshold; $250,000 married filing jointly, $125,000 married filing separately) the 0.9% Additional Medicare Tax applies: max(0, base − 200,000) × 0.9%, shown on its own line for a single filer. The set-aside is SE tax plus Additional Medicare Tax plus income tax, and the effective rate is that total divided by net earnings. All amounts are in US dollars, and the bracket is a single flat percentage you choose, so the standard deduction, credits, state tax and other income are not modelled. Other countries tax freelancers differently.

Common mistakes

• Entering the bracket as a decimal (0.22) instead of a percentage (22). The field expects a value from 0 to 100, so 0.22 means 0.22% and the income tax almost vanishes.
• Typing revenue as income but forgetting expenses. Self-employment tax is charged on net earnings, so leaving expenses at zero overstates the set-aside.
• Entering your marginal bracket as if it applied to everything. The tool applies one flat rate to all net earnings, so a rate from the top of your bracket overestimates the tax on the lower slices.
• Treating the result as a full tax bill. State tax, the standard deduction, credits and income from a W-2 job are not included.
• Expecting a result for a loss. If expenses exceed income, net is zero and every figure shows $0.00.