Self-Employment Tax Calculator (2026)

The two taxes every freelancer pays

Self-employed income is hit by two separate federal taxes, and confusing them is the #1 source of freelancer tax surprises:

• Self-employment (SE) tax — 15.3%. This is Social Security (12.4%) and Medicare (2.9%) combined. Employees split it with their employer; you pay both halves. It applies from the first dollar of profit — there's no standard deduction against it.
• Federal income tax — 10% to 37%. The same progressive brackets everyone pays, applied after the standard deduction, half of your SE tax, and the QBI deduction.

This is why a freelancer with $85,000 of profit owes real money even though "the 22% bracket" sounds manageable — the 15.3% runs in parallel underneath.

How the 2026 calculation works, step by step

1. SE tax base: net profit × 92.35%. (The 7.65% haircut mirrors the employer half employees never see.)
2. Social Security portion: 12.4% of the base, but only up to the 2026 wage cap of $184,500 — and W-2 wages you earn use up that cap first.
3. Medicare portion: 2.9% of the whole base, uncapped, plus 0.9% Additional Medicare Tax on combined earnings above $200,000 (single) / $250,000 (joint).
4. Income tax: profit − half your SE tax − standard deduction ($16,100 single / $32,200 joint) − QBI deduction, then run through the 2026 brackets.
5. QBI deduction: up to 20% of qualified business income — for most freelancers under the income thresholds, a straight 20% off before income tax. Made permanent by the 2025 tax law.

The freelancer's cash-flow system

Knowing the number is half the job; having the cash on the due dates is the other half. The system that works:

1. Open a separate "tax" savings account. Not a category in your head — an actual account.
2. Transfer your effective rate from every payment the day it arrives. The calculator's "per $1,000 earned" figure is exactly this number.
3. Pay quarterly from that account: April 15, June 15, September 15, and January 15. Pay online in minutes at IRS Direct Pay.
4. Use the safe harbor if income is lumpy: pay 100% of last year's total tax (110% if prior AGI was over $150,000) in four even installments, and no underpayment penalty applies even if you earn far more this year.

Deductions freelancers most often miss

• Home office: the simplified method is $5 per square foot up to 300 sq ft — no depreciation records needed.
• Health insurance premiums: deductible above-the-line for the self-employed, including spouse and dependents.
• Retirement plans: a Solo 401(k) shelters far more than an IRA — up to $70,000+ depending on profit — and cuts income tax now (though not SE tax). Model growth with the compound interest calculator.
• Half of SE tax: automatic, but worth knowing it exists — this calculator applies it for you.
• Software, mileage, professional fees, business insurance: ordinary and necessary business costs — track them year-round, not in April.

Income that swings month to month makes a cash cushion non-negotiable — freelancers should target the higher end of the emergency fund range.