Free Self-Employment Tax Calculator

When you work for yourself, there is no employer paying half of your Social Security and Medicare tax, so the IRS collects both halves from you directly through self-employment tax. This calculator applies the current rates to your net self-employment earnings so you can budget for the bill and, ideally, set money aside quarterly.

Results

Net earnings (92.35%)$73,880.00
Social Security (12.4%)$9,161.12
Medicare (2.9%)$2,142.52
Self-employment tax$11,303.64
Deductible half (Schedule 1)$5,651.82
Effective rate on profit14.13%
  • Social Security81.0%
  • Medicare19.0%

Disclaimer: This calculator provides estimates only and does not constitute tax advice. Rates and thresholds change; confirm the current figures with your tax authority or accountant.

What the Self-Employment Tax Calculator does

Self-employment tax is the US federal tax that funds Social Security and Medicare for people who work for themselves, combining what would otherwise be the employee and employer shares of payroll tax into a single tax on net earnings from self-employment, reported and paid alongside income tax.

Methodology and formula

Net earnings from self-employment = Net profit x 92.35%. Social Security portion = lesser of (Net earnings x 12.4%) or (Social Security wage base x 12.4%). Medicare portion = Net earnings x 2.9% (no cap). Additional Medicare Tax = 0.9% on combined wages and self-employment income above the applicable threshold ($200,000 single / $250,000 married filing jointly). Total self-employment tax = Social Security portion + Medicare portion + any Additional Medicare Tax.

Worked example

Inputs
Net profit from Schedule C: 80,000; single filer with no other wages.
Result
Net earnings from self-employment 73,880; Social Security tax (12.4%) 9,161; Medicare tax (2.9%) 2,143; total self-employment tax about 11,304.

Because net earnings of 73,880 fall below the Social Security wage base, the full 12.4% applies to that amount; someone with net earnings well above the wage base would only pay the 12.4% portion up to the base, with every dollar above it taxed at the 2.9% Medicare rate alone.

When to use this tool

Use this calculator to estimate the federal self-employment tax due on your net earnings so you can set aside quarterly payments. Use the Freelance Hourly Rate Calculator to build this tax burden into the rate you charge clients, and the Pay Stub Generator if you also need to document owner or contractor payments.

About the Self-Employment Tax Calculator

Why the rate is 15.3% and not just the Medicare or Social Security rate

Employees have 7.65% of pay withheld for Social Security and Medicare, and their employer matches it with another 7.65%, for a combined 15.3%. A self-employed worker is both employee and employer, so self-employment tax charges the full 15.3% (12.4% Social Security up to the wage base, plus 2.9% Medicare with no cap) directly on their own net earnings.

The 92.35% adjustment, and why it exists

Self-employment tax is calculated on 92.35% of net profit, not 100%. This mirrors the fact that an employer's matching payroll tax contribution is not counted as taxable wages for an employee, so the self-employed calculation reduces the base by roughly the employer-equivalent share before applying the rate, keeping the comparison fair between the two groups.

The Social Security wage base cap

The 12.4% Social Security portion only applies up to an annual wage base limit that is adjusted most years for inflation; net earnings above that limit are not subject to the Social Security portion at all. The 2.9% Medicare portion, by contrast, has no cap and applies to every dollar of net earnings from self-employment, no matter how high.

Deducting the employer-equivalent half and paying quarterly

You can deduct half of your self-employment tax as an adjustment to income on your federal return, which roughly mirrors how an employer's share is not taxed to an employee. Because no employer withholds this tax throughout the year, most self-employed people must make quarterly estimated tax payments to the IRS to avoid an underpayment penalty at filing time.

Frequently asked questions

What is the self-employment tax rate?

It is 15.3% total: 12.4% for Social Security, applied only up to the annual Social Security wage base, plus 2.9% for Medicare, which applies with no cap to all net self-employment earnings. High earners may also owe an extra 0.9% Additional Medicare Tax above a set income threshold.

Why is self-employment tax calculated on 92.35% of net profit?

The 92.35% figure approximates the employer-equivalent share that would not be taxed if you were an employee, since an employer's matching payroll contribution is not counted as the employee's taxable wages. Applying the rate to 92.35% rather than 100% keeps self-employed and employee tax treatment roughly comparable.

Is there a cap on self-employment tax?

Only the Social Security portion (12.4%) is capped, and only up to the annual Social Security wage base. The Medicare portion (2.9%) has no cap and applies to all net self-employment earnings, and an Additional Medicare Tax of 0.9% can apply above set income thresholds.

Can I deduct any of my self-employment tax?

Yes. You can deduct half of your self-employment tax as an adjustment to income when calculating your federal adjusted gross income, which mirrors how an employer's share of payroll tax is not taxed to an employee. This deduction reduces income tax owed but not the self-employment tax itself.

Do I need to make quarterly estimated payments?

Generally yes, if you expect to owe $1,000 or more in tax for the year and no one is withholding tax on your behalf. Self-employment income has no automatic withholding, so most self-employed workers pay estimated federal tax, covering both income tax and self-employment tax, four times a year.

Does self-employment tax replace income tax?

No. Self-employment tax funds Social Security and Medicare only and is calculated separately from federal income tax. You owe both: income tax on your net profit at your regular tax bracket, plus self-employment tax on your net earnings from self-employment as calculated here.

Related Tax & Compliance Tools

Other free tools in the tax & compliance silo.