Free Self-employment Tax Calculator (+ Guide)

What is a self-employment tax calculator?

A self-employment tax calculator works out the Social Security and Medicare tax that freelancers and business owners pay on their earnings.

An employer would pay half of these for an employee, so when you work for yourself you pay both halves.

How it works

The calculator works it out on your device, and your numbers stay there.

The rates

IRS Topic 554 sets the rate at 12.4% for Social Security and 2.9% for Medicare, on 92.35% of your net earnings.

Social Security stops at the year's wage base, $184,500 for 2026 in Publication 15. Medicare has no cap.

The 0.9% Additional Medicare Tax

IRS Topic 560 adds 0.9% on self-employment income above $200,000, or $250,000 married filing jointly and $125,000 married filing separately.

W-2 wages lower that threshold first, so the calculator takes them into account.

The deduction

Topic 554 lets you deduct half your self-employment tax when you figure your adjusted gross income.

That lowers your income tax, but not the self-employment tax itself.

A worked example

Here's the example the calculator loads: $60,000 of net earnings, single, no W-2 wages.

92.35% of it is $55,410. Social Security is $6,870.84 and Medicare $1,606.89, for $8,477.73 in all, about 14.1% of your earnings.

You'd deduct $4,238.87 from your income, and a quarter's share is about $2,119.43.

Mistakes to avoid

These are the slips that come up most.

• Taxing your full net earnings instead of 92.35% of them
• Forgetting to deduct half the tax from your income
• Ignoring the W-2 wages that use up part of the Social Security cap
• Waiting until April instead of setting money aside every quarter

Who is the self-employment tax calculator for?

It's for freelancers, creators and anyone with a side business, and these tools help around it.

• Freelance rate calculator – for a rate that covers your taxes
• Profit margin calculator – for what each sale leaves you
• Hourly to salary calculator – for your rate as a year's pay

Set the tax aside as you earn it, and the April bill stops being a surprise.