Self-Employment Tax Calculator (Social Security + Medicare)
Enter your net self-employment profit to see the Social Security and Medicare tax you'll owe for 2026, split into its parts, plus the deductible half that lowers your income tax. Add W-2 wages if you also have a day job and the wage base is shared correctly.
Income minus business expenses (Schedule C net profit)
Sets the additional Medicare tax threshold
Day-job wages that already had Social Security tax withheld
Self-employment tax
$11,304
on $73,880 of net earnings (92.35% of profit)
Deductible half
$5,652
lowers your income tax as an above-the-line deduction, not the SE tax itself
Social Security portion
$9,161
applies until net earnings reach the $184,500 wage base
Medicare portion
$2,143
no wage cap: this part applies to all net earnings
Effective rate: about 14.1% of your net profit. The deductible half above does not reduce this bill; it reduces the income tax calculated afterward.
SE tax at common profit levels
| Net profit | SE tax | Deductible half | Share of profit |
|---|---|---|---|
| $25,000 | $3,532 | $1,766 | 14.1% |
| $50,000 | $7,065 | $3,532 | 14.1% |
| $75,000 | $10,597 | $5,299 | 14.1% |
| $100,000 | $14,130 | $7,065 | 14.1% |
| $150,000 | $21,194 | $10,597 | 14.1% |
Rows use your filing status. The share of profit barely moves because both rates are flat until net earnings work through the Social Security wage base.
Educational estimate for the 2026 tax year, not tax advice. Federal figures follow IRS inflation adjustments; state estimates use statewide rates and standard deductions only and exclude local income taxes (city, county, school district), State Disability Insurance, and credits. Where a state publishes separate married tables, married thresholds may be approximated. Verify your exact withholding with a tax professional or your payroll provider.
How the math works: a haircut, then two flat rates
Self-employment tax starts by multiplying your net profit by 92.35%, which turns profit into "net earnings." That factor exists for fairness: an employer pays its half of payroll taxes before an employee's wages are counted, so the self-employed get an equivalent trim before the rates apply. Two flat rates then hit those net earnings: 12.4% for Social Security, which stops once earnings reach the annual wage base ($184,500 in 2026, shared with any W-2 wages), and 2.9% for Medicare, which never stops. A small additional Medicare rate applies above a high-income threshold, and the calculator includes it when it triggers.
The employer half you never saw
The combined 15.3% stings because employees only ever see half of it on a pay stub; the other half is paid invisibly by the employer. Working for yourself, you are the employer too, so both halves land on your return. Congress softened this with the deductible half: one half of the base SE tax comes off your income as an above-the-line deduction. Important nuance: that deduction reduces the income tax calculated afterward, it does not reduce the SE tax itself. Your SE bill is what it is; the deduction just keeps that money from being income-taxed as well.
A worked example at $80,000 of profit
Say a freelance designer nets $80,000 after expenses, filing single. Net earnings come to $73,880. Social Security takes $9,161, Medicare takes $2,143, for a total SE tax of $11,304. The deductible half, $5,652, then reduces taxable income before income tax is figured. So the real cost of self employment here is the $11,304 bill, partially offset by the income tax saved on that deduction.
When this matters: nobody withholds for you
Employees have this tax quietly withheld every payday. Freelancers get the full bill at filing time unless they pay as they go, which is why estimated taxes exist. If your SE tax plus income tax will be meaningful, run the quarterly tax calculator next and set the money aside per project, not per April. And when you price your work, bake this tax into the rate itself: the freelance rate calculator treats it as a cost of doing business, which it is.
Frequently asked questions
What is self-employment tax?
It is how freelancers, contractors, and business owners pay Social Security and Medicare. Employees split these taxes with their employer through payroll withholding; when you work for yourself you are both parties, so you pay both halves yourself, a combined 15.3% on most of your net profit. It is separate from, and comes on top of, regular federal income tax.
Why isn't all of my profit subject to SE tax?
Only 92.35% of net profit counts as net earnings. The adjustment mirrors the W-2 world, where the employer's half of payroll tax is paid before wages are measured, so the self-employed get an equivalent haircut before the rates apply. The calculator applies it automatically.
I also have a W-2 job. Do I pay Social Security twice?
Not on the same dollars. Social Security tax stops once total wages plus net earnings reach the annual wage base ($184,500 for 2026). Wages from your job use up that base first, so only the remainder of the base applies to your self-employment earnings. Medicare has no cap, so its part continues on everything.
Does the deductible half reduce my self-employment tax?
No. Half of the base SE tax is an above-the-line deduction that lowers your adjusted gross income, which shrinks your income tax bill. The SE tax itself is unchanged; think of the deduction as a partial rebate that shows up on the other side of your return.
How accurate is this calculator?
Educational estimate for the 2026 tax year, not tax advice. Federal figures follow IRS inflation adjustments; state estimates use statewide rates and standard deductions only and exclude local income taxes (city, county, school district), State Disability Insurance, and credits. Where a state publishes separate married tables, married thresholds may be approximated. Verify your exact withholding with a tax professional or your payroll provider.
Does this calculator save my numbers?
No. Everything runs in your browser and nothing you type is stored or sent anywhere.
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