Applies Schedule SE rules: 92.35% factor, Social Security 12.4% up to the 2025 wage base, Medicare 2.9% on all SE earnings, plus the 0.9% Additional Medicare tax by filing status. Shows your half-SE deduction.
This calculator estimates your 2025 self-employment (SE) tax using the same building blocks as Schedule SE. It takes your net profit and applies the 92.35% factor to approximate “SE earnings,” coordinates the Social Security portion (12.4%) with any W-2 Social Security wages you already have, applies Medicare (2.9%) on all SE earnings, and checks whether the 0.9% Additional Medicare tax applies based on filing status and total earned income. You’ll also see the above-the-line half-SE tax deduction that reduces AGI.
Enter your filing status, Schedule C/F/K-1 profit, and W-2 wage boxes exactly as shown on your forms. The tool will show the wage-base room left for Social Security, the Medicare base, and the Additional Medicare threshold math, then summarize SE tax, any extra 0.9% amount, and your total. Use Download CSV to save the breakdown for your records or to share with a preparer.
Planning beyond SE tax? Pair this with our Federal Income Tax Calculator for your overall federal estimate, or check Capital Gains & Qualified Dividends if you have investment income. Filing in New York? See the combined state/city view in our NY State & NYC calculator.
Heads-up: This is an estimator, not advice. Special rules (ministers, church employees, optional methods, sick pay, repayments, etc.) can change results. When in doubt, follow the official Schedule SE and Form 8959 instructions or talk with a pro.
| Self-employment tax (SS + Medicare) | — |
|---|---|
| Additional Medicare tax (0.9%) | — |
| Total (SE tax + Additional Medicare) | — |
Start with your net self-employment profit from Schedule C (or farm Schedule F, or partnership K-1 SE income). Enter W-2 Social Security wages (Boxes 3 + 7) and W-2 Medicare wages (Box 5) so the tool can coordinate your Social Security cap and the Additional Medicare threshold across both job and business income. Hit Calculate to see the Social Security portion (12.4%), Medicare portion (2.9%), the 0.9% Additional Medicare tax if your earned income clears the threshold, and your above-the-line “half-SE” deduction.
If you also need an estimate of your regular federal income tax on wages or sole-prop income, pair this tool with the Federal Income Tax Calculator. For investment income, check the Capital Gains & Qualified Dividends Calculator. Filing in New York? Try our New York State & NYC calculator.
The “Self-employment tax (SS + Medicare)” line combines the two payroll-style pieces that apply to self-employed earnings. First, we apply the IRS’s 92.35% factor to your net profit to approximate the portion treated as wages for payroll tax purposes. Then we split that base into (1) Social Security at 12.4% up to the annual wage base, coordinated with your W-2 Social Security wages, and (2) Medicare at 2.9% with no cap. The “Additional Medicare tax (0.9%)” is a separate income tax on earned income above a filing-status threshold—it doesn’t increase your half-SE deduction and doesn’t count toward Social Security credits.
The table shows the exact bases used for each component. The “Half-SE deduction” you’ll see in the summary equals 50% of the SE tax (Social Security + 2.9% Medicare only). You can generally claim that on Schedule 1, which lowers your AGI for other calculations. Export the CSV for your records or to share with a preparer.
| Component | Base | Rate | Tax |
|---|
The half-SE tax deduction equals 50% of the SE tax (not including the 0.9% Additional Medicare tax).