Self-Employment Tax Calculator (2025-2026)

What self-employment tax is

When you have a regular job, Social Security and Medicare come out of every paycheck, and your employer pays a matching amount you never see. Go freelance and that arrangement disappears: you are now both the worker and the employer, so you cover both halves yourself. That combined contribution is self-employment tax. The rate is 15.3%: 12.4% for Social Security and 2.9% for Medicare.

This is the surprise that catches many first-year freelancers off guard, because it lands before income tax, not instead of it. If you budget only for income tax, your set-aside can be short before state tax or federal brackets even enter the picture.

Why the calculator takes 92.35% first

Look at the first line of the result and you will see your profit shrink to 92.35% of itself before any rate is applied. That is not a glitch. An employee never pays Social Security and Medicare on the employer’s share of the tax, so the rules let the self-employed knock off an equivalent slice before the 15.3% is charged. That is why the real bite on your profit comes out around 14.1% rather than a flat 15.3%, unless the Social Security cap or Additional Medicare Tax changes the mix.

Where the 15.3% goes

• Social Security (12.4%) only applies up to a yearly wage cap. For 2025 that cap is $176,100; for 2026 it is $184,500, per the Social Security Administration’s Contribution and Benefit Base table.
• Medicare (2.9%) has no cap. It applies to every dollar of net earnings subject to the tax.
• Additional Medicare Tax (0.9%) applies above the statutory thresholds: $200,000 for single/head of household, $250,000 for married filing jointly, and $125,000 for married filing separately.

If you also draw a W-2 salary, those wages use up the Social Security cap first. Enter them in the optional field and the tool will stop charging the 12.4% portion once your combined earnings clear the cap.

The half you get back

Self-employment tax feels heavier than it ends up being because you can deduct one-half of it when you work out adjusted gross income. It does not shrink the self-employment tax itself, but it lowers the income your income tax is calculated on. The result shows this deductible half on its own line so you can use it as a planning figure.

This is not your whole tax bill

Read this part carefully: self-employment tax sits on top of federal income tax, and usually on top of state or local tax. This tool deliberately estimates only the self-employment piece, because that part is mostly the same arithmetic for everyone. It stays out of income-tax brackets, the standard deduction, the qualified business income deduction, credits and state rules, all of which depend on your full financial picture.

For a practical budgeting habit, pair this number with how much to set aside for tax, then make sure the rate you charge survives the tax set-aside using the freelance hourly rate calculator.

If you are comparing an independent-contractor offer with employment, run the self-employment layer first and then read how much higher a 1099 rate should be than a W-2 salary. If this is your first year, the guide to first-year freelancer quarterly taxes explains when payments actually start.

The tax estimate also belongs in your pricing, not just your filing folder. The hidden costs of freelancing show where that extra load comes from, and the mileage vs actual car expenses guide is useful if vehicle deductions are part of your net-profit estimate.

A worked example

Say you cleared $60,000 of net profit freelancing in 2025, filing single, with no day job. First the profit drops to 92.35%, which gives $55,410 of net earnings. The full 15.3% applies because you are nowhere near the $176,100 Social Security cap, giving about $8,478 of self-employment tax. Half of that, about $4,239, is deductible against income tax. Spread across four quarterly payments, the self-employment slice is roughly $2,119 each.

The most useful version of that example is a side-by-side one: what happens at $60,000 versus $80,000, or 2025 versus 2026? Run one case, hit Save scenario, change the inputs, and save again — the calculator keeps your last six scenarios in this browser and shows them in a comparison table under the results. Download CSV exports the current inputs and every saved scenario, with the full line-by-line breakdown, straight into a spreadsheet. Everything stays on your device: saved scenarios live in your browser’s local storage, and the CSV is generated locally, never uploaded. And if you run a site for freelancers yourself, you can embed this calculator on your own pages for free.

Assumptions and limitations

• U.S. federal self-employment tax only. No federal income tax, state tax, city tax, credits or personal deductions.
• One combined net profit. Enter your total net self-employment earnings after business expenses.
• The two W-2 fields serve different rules. Enter Social Security wages from Form W-2 box 3 for the annual wage cap. Enter Medicare wages and tips from box 5 for the Additional Medicare threshold; if you file jointly, the box 5 field should include both spouses’ amounts.
• The Additional Medicare line covers self-employment income only. It does not calculate any separate Additional Medicare Tax that may be due on W-2 wages themselves or reconcile employer withholding; Form 8959 handles the complete calculation.
• Net profit must already be net. Self-employment tax is charged on profit, not gross revenue.
• Figures are estimates. Rounding and your full return can move the final number.

The constants under the hood (and when they change)

A tax calculator is only as trustworthy as its constants, so here are the exact values this tool computes with, and where each one comes from. Most of them are set by statute and haven’t moved in years; only one changes on a schedule.

Change log:

• 2026 tax year: Social Security wage base raised from $176,100 to $184,500, per the SSA’s annual cost-of-living adjustment (COLA) announcement. No other constant changed.
• Last verified: 2026-06-29, against the IRS and SSA pages listed in the sources below.

The Social Security wage base is the value that moves every January — the SSA announces the new figure each fall, and this tool is updated when it takes effect. Every figure above traces back to the IRS and SSA pages in the Sources section further down this page.