What is Self-Employment Tax Calculator (Schedule SE)?
Free Schedule SE calculator using the IRS 92.35% × 15.3% formula with SS wage base ($176,100 for 2025), Medicare 2.9% uncapped, and Additional Medicare 0.9% above the IRC § 1401(b)(2) threshold. Includes the deductible-half above-the-line offset and quarterly 1040-ES payment suggestion. No signup required.
SE Tax runs entirely in your browser using JavaScript (browser). Your data never leaves your device.
Free Self-Employment Tax Calculator (Schedule SE)
Compute self-employment tax under IRC § 1401 / Schedule SE: SE earnings = net SE × 92.35%; SS portion = 12.4% capped at the wage base (reduced by any W-2 wages); Medicare = 2.9% uncapped; Additional Medicare = 0.9% above $200k single / $250k MFJ. Also shows the deductible half (above-the-line on Schedule 1 line 15) and the suggested quarterly 1040-ES payment.
Your self-employment income
From Schedule C line 31 or K-1 (partnership SE income). This is gross revenue minus business expenses, BEFORE SE tax.
If you also have a W-2 job, those wages use up part of your Social Security wage base. Leave at 0 if pure freelancer.
Self-employment tax
$11,304
≈ $2,826 per quarter (1040-ES).
Above-the-line deduction
$5,652
Half of SE tax is deductible from gross income on Schedule 1 line 15. At a 24% marginal rate, that saves you $1,356 in federal income tax.
SE tax owed
$11,304
$2,826 per quarter · $5,652 deduction
SE tax
$11,304
Quarterly
$2,826
The Schedule SE formula in plain English
Self-employed people pay both halves of FICA (Social Security + Medicare) on their net business income. Where a W-2 employee pays 7.65% and their employer pays the matching 7.65%, you pay the full 15.3% — that's self-employment tax. The exact computation under IRC § 1401 and Schedule SE:
- SE earnings = net SE income × 92.35%. This is the IRC § 1402(a)(7) multiplier — it bakes in the deductible-half-of-SE-tax offset so that you don't pay SE tax on the part of your income that the SE tax itself reduces.
- SS portion = SE earnings × 12.4% — capped at the SS wage base ($176,100 for 2025, per SSA). If you have W-2 wages from a job, those wages use up part of the cap and only the remainder is available for your SE earnings.
- Medicare portion = SE earnings × 2.9% — uncapped. The full 2.9% (both halves of the 1.45% Medicare tax) applies to every dollar.
- Additional Medicare = 0.9% on combined W-2 + SE earnings above $200k single / $250k MFJ (IRC § 1401(b)(2)).
- Total SE tax = SS + Medicare + Additional Medicare.
The good news: half of SE tax is deductible from gross income on Schedule 1 line 15 (IRC § 164(f)). It's above-the-line, so you get it whether you itemize or take the standard deduction. At a 24% federal marginal rate, that deduction saves you roughly 24% × (SE tax ÷ 2) in regular income tax.
Common SE tax mistakes
- Not paying quarterly. SE tax + income tax must be paid as you earn through quarterly 1040-ES vouchers (4/15, 6/15, 9/15, 1/15). The underpayment penalty (IRC § 6654) bites if you withhold less than 90% of current-year tax OR 110% of prior-year tax (110% for AGI > $150k).
- Forgetting the deductible half. Many DIY filers compute SE tax but forget the Schedule 1 line 15 deduction. At 24% bracket, that's 24% × $7,000 SE tax / 2 = $840 of tax you owe that you shouldn't.
- Confusing SE tax with income tax. They're separate. A 1099-only person earning $80k owes ~$11k SE tax PLUS ~$10k income tax. Total tax bill is ~26%, not 15.3%.
- Not contributing to retirement. SEP-IRA, Solo 401(k), or SIMPLE IRA contributions reduce your income tax (not your SE tax). A SEP at 20% of net SE income shelters $16,000 of income on $80k SE — directly reducing your federal income tax bill.
- Missing the QBI deduction. Qualified Business Income deduction (IRC § 199A) can knock 20% off your pass-through income for federal income tax purposes (subject to phase-outs). Doesn't reduce SE tax but a meaningful income-tax benefit.
Frequently Asked Questions
What is self-employment tax?+
Self-employment tax is the combined Social Security + Medicare tax that self-employed people pay on net business income. W-2 employees pay 7.65% (half of FICA) and their employer pays the matching 7.65%; self-employed people pay both halves = 15.3%. Codified at IRC § 1401.
What is the 92.35% multiplier?+
Per IRC § 1402(a)(7), SE earnings are computed as net SE income × 92.35%. This adjusts for the fact that half of SE tax is deductible — the multiplier ensures you don't pay SE tax on the part of your income that the SE tax itself reduces.
Why is the deductible half not a credit?+
It's an above-the-line deduction on Schedule 1 line 15 (IRC § 164(f)) — reduces your AGI for regular federal income tax purposes. Not a dollar-for-dollar credit against SE tax. Still valuable: at 24% marginal rate, $7,000 SE tax → $3,500 deduction → $840 income-tax savings.
Do I need to pay SE tax quarterly?+
Yes, in most cases. The IRS expects quarterly 1040-ES vouchers (4/15, 6/15, 9/15, 1/15) covering both income tax and SE tax. The safe-harbor rule (IRC § 6654) waives the underpayment penalty if you pay 90% of current-year tax or 110% of prior-year tax (110% for AGI > $150k).
What if I also have W-2 wages?+
W-2 wages use part of your $176,100 SS wage base — only the remainder is available for SE earnings. Medicare 2.9% still applies to all SE earnings regardless of W-2. If combined wages exceed the Additional Medicare threshold ($200k single / $250k MFJ), the 0.9% applies to the excess.
Can I deduct business expenses?+
Yes — net SE income is your gross revenue minus ordinary and necessary business expenses (Schedule C). Home office, mileage, internet, professional fees, retirement contributions, health insurance premiums — all reduce net SE income, which in turn reduces SE tax. Major SE-tax-reduction lever for most freelancers.
How does an S-corp election change SE tax?+
In an S-corp, you pay yourself a reasonable salary (W-2) and take the rest as distributions. Only the salary is subject to FICA (employer + employee paying 7.65% each = 15.3% total). The distributions are NOT subject to SE tax. This is a major planning lever for SE income above ~$60k. Setup costs and complexity make it worthwhile only above ~$80k of net SE income.
Is my data stored?+
No. All math runs in your browser. Your business income never leaves your device.
You might also like
Browse all 4 Taxes tools →Freelance Rate Calculator
Calculate the hourly rate you actually need to charge as a freelancer
Paycheck Calculator
Calculate your take-home pay after taxes instantly
Invoice Generator
Create and download professional invoices instantly