How the self-employment tax calculator works
Self-employment (SE) tax is how freelancers and sole proprietors pay into Social Security and Medicare. Employees split these taxes with their employer; the self-employed pay both halves.
Social Security = 12.4% of net earnings up to $184,500 (2026 wage base, minus W-2 wages)
Medicare = 2.9% of all net earnings
Additional Medicare = 0.9% above $200,000 single / $250,000 joint
The 92.35% factor gives you the equivalent of the employer-half deduction an employee would get. You can then deduct half of the SE tax from your income for income-tax purposes (but not from SE tax itself). W-2 wages count toward the Social Security wage base first, which reduces the SE Social Security tax for people with both kinds of income. SE tax is in addition to regular income tax.
Worked example
A freelancer with $80,000 of net profit has net earnings of $73,880. Social Security is 12.4% of that ($9,161) and Medicare 2.9% ($2,143), for a total SE tax of $11,304. Half, $5,652, is deductible on Form 1040. Quarterly estimated payments for SE tax alone would be about $2,826.
Tax estimates use 2026 federal figures and simplified rules. They are not tax advice; check with a tax professional.
Frequently asked questions
What is the self-employment tax rate for 2026?
15.3% on 92.35% of net earnings: 12.4% Social Security up to the $184,500 wage base and 2.9% Medicare on everything, plus 0.9% Additional Medicare Tax above $200,000 for single filers.
Who has to pay self-employment tax?
Anyone with $400 or more of net self-employment earnings in a year.
Is self-employment tax deductible?
Half of it is deductible as an adjustment to income, which lowers income tax.
Does SE tax replace income tax?
No. It is in addition to federal and state income tax.
Updated October 2026. Results are estimates for education, not financial or medical advice. All math runs in your browser; nothing you type is sent anywhere.