Self-Employed Tax Calculator
The 15.3% self-employment tax is not flat: the 12.4% Social Security part stops at an annual wage base (about $176,100), and W-2 wages you already paid Social Security on reduce it further. This calculator splits SE tax into its two parts and shows the deductible half — the number that lowers your income tax.
How the SE tax split works
Only 92.35% of net self-employment income is subject to SE tax — the law excludes the equivalent of the employer half.
The Social Security portion (12.4%) applies only until combined wages hit the annual wage base (~$176,100 for 2025, indexed each year). Above it, only the 2.9% Medicare portion continues.
Half of your SE tax is deductible against income tax — it reduces AGI even if you take the standard deduction. That's why the 'deductible half' output matters.
Frequently asked questions
Why does my SE tax rate drop at high income?
The 12.4% Social Security part stops at the wage base (~$176k). Beyond it you only pay the 2.9% Medicare portion, so the blended rate falls.
I have a W-2 job and freelance on the side — do I pay double Social Security?
No. W-2 wages already covered by Social Security reduce the self-employment income subject to the 12.4% part. Enter your W-2 SS wages to see the offset.
What if my net income is under $400?
You owe no self-employment tax below $400 of net earnings — the calculator applies that rule automatically.
Related tools
- Rules: IRS Schedule SE; Social Security wage base $176,100 (2025), indexed annually. Estimate only.
Last updated: 2026-09-08