SE tax calculator

Calculate your self-employment tax.

The 15.3% rate with the 92.35% adjustment, Social Security wage base cap, Medicare, and the Additional Medicare surtax for high earners. Updated for 2026.

Your numbers

Net SE income is your gross 1099 income minus business expenses and the mileage deduction.

Gross 1099 minus mileage deduction and business expenses

Counts toward the Social Security wage base cap

Determines the Additional Medicare Tax threshold

How SE tax actually works

Self-employment tax is a flat 15.3% rate broken into two parts: 12.4% for Social Security and 2.9% for Medicare. But the actual calculation has three twists that change the number.

1. The 92.35% adjustment

Before applying any rates, you multiply your net SE income by 92.35%. The 7.65% reduction is the "employer half" of FICA you don't actually have. So if you netted $40,000 in SE income, you apply SE tax rates to $36,940 — not $40,000.

2. The Social Security wage base cap

The 12.4% Social Security portion only applies to the first $176,100 (2026) of combined W-2 wages and adjusted SE income. Above that cap, you stop owing Social Security tax. The Medicare portion has no cap — it applies to every dollar.

If you have a day job: your W-2 wages count toward this cap. The calculator subtracts them to compute how much SS cap is left for your SE income.

3. The Additional Medicare Tax (high earners)

If your combined SE + W-2 income exceeds:

  • $200,000 (single or head of household)
  • $250,000 (married filing jointly)
  • $125,000 (married filing separately)

...an additional 0.9% Medicare surtax kicks in on the amount above the threshold. The calculator handles this. For most rideshare and delivery workers it won't apply, but for high-earning freelancers it can.

The half-SE-tax deduction. Half of your SE tax is deductible from your federal taxable income on Schedule 1. It doesn't lower the SE tax itself, but it does lower your federal income tax bill. The calculator shows this amount on the breakdown so you can plug it into the quarterly tax calculator if you want the full picture.

The simple version

If you don't want to think about caps and surtaxes (and your net SE income is under ~$140K), the rule of thumb is:

SE tax ≈ Net SE × 14.13%

That's the 15.3% rate times the 92.35% adjustment, with no cap math. Good enough for back-of-envelope planning.

Related guides

FAQ

What is self-employment tax?

SE tax is the self-employed version of the FICA payroll tax. W-2 employees pay 7.65% (6.2% Social Security + 1.45% Medicare) and their employer matches it for a combined 15.3%. Self-employed people are both employee and employer, so they pay the full 15.3% themselves. This is separate from federal income tax.

What's the 92.35% adjustment?

Before applying the 15.3% SE tax rate, the IRS lets you multiply your net SE income by 92.35%. This roughly mirrors how employers exclude their share of FICA from your taxable wages. Net effect: instead of 15.3% on the full amount, you pay 15.3% × 92.35% ≈ 14.13% effective rate on gross net SE income.

What's the Social Security wage base?

For 2026, the Social Security portion of SE tax (12.4%) only applies to the first $176,100 of combined wages and SE income. Above that, you only owe the 2.9% Medicare portion. The wage base goes up most years with inflation.

What's the Additional Medicare Tax?

On top of the standard 2.9% SE Medicare, an additional 0.9% Medicare surtax applies to SE income (combined with wages) above $200,000 for single filers, $250,000 for married filing jointly, or $125,000 for married filing separately. The calculator includes this for high earners.

How does the half-SE-tax deduction work?

You can deduct half of your SE tax from your federal income tax (the "above-the-line" deduction on Schedule 1). It doesn't reduce the SE tax itself, but it reduces your income tax. The full calculation of how this interacts with your bracket is handled in the quarterly tax calculator.