A self-employment tax calculator helps freelancers, independent contractors, and 1099 workers estimate what they owe the IRS each year. Unlike W-2 employees whose employers withhold taxes, self-employed individuals must calculate and pay Social Security, Medicare, and income tax themselves — plus make quarterly estimated payments to avoid penalties.
Enter Your Income Details
Your 1099 / freelance earnings minus direct business costs
Home office, equipment, software, mileage, etc.
If you also have a W-2 job — used for bracket calculation
Tax Breakdown
2025 Quarterly Estimated Payments
Take-Home Income Estimate
Estimate only. This calculator covers federal self-employment and income tax using 2025 rates. It does not include state income taxes, health insurance deductions, retirement contributions, or other credits. Consult a tax professional or CPA for personalized advice.
How to Use This Self-Employment Tax Calculator
Freelancers and 1099 contractors face a tax situation that is fundamentally different from salaried employees. Because no employer withholds taxes from your paychecks, you are responsible for calculating and paying your own Social Security, Medicare, and federal income taxes — plus submitting quarterly estimated payments to avoid IRS penalties. This self-employment tax calculator does all that math for you using 2025 federal rates.
Step 1: Enter Your Net Self-Employment Income
Start with your total 1099 or freelance earnings for the year, then subtract any direct cost of goods sold. This is your net self-employment income — the figure the IRS uses as the starting point for SE tax. Do not subtract general business expenses here; enter those separately in the Business Deductions field.
Step 2: Add Business Deductions
Enter your estimated deductible business expenses: home office, business-use vehicle mileage (at 70 cents per mile for 2025), software subscriptions, professional development, equipment, and business insurance. These deductions reduce your net SE income before tax is calculated, which lowers both your SE tax and your income tax bill.
Step 3: Select Your Filing Status and W-2 Income
Choose whether you file as Single, Married Filing Jointly, Married Filing Separately, or Head of Household — this determines both your standard deduction and the federal income tax brackets applied to your taxable income. If you also have W-2 wages from an employer, enter that amount so the calculator can use the combined income for accurate bracket placement.
How SE Tax Is Calculated
The IRS applies SE tax to 92.35% of your net self-employment income. This adjustment mirrors the employer-side deduction W-2 employees receive. The resulting figure is your SE taxable earnings. The Social Security portion is 12.4% of those earnings, up to the 2025 wage base of $176,100. The Medicare portion is 2.9% on all earnings, with an additional 0.9% if your total income exceeds $200,000 (single) or $250,000 (married filing jointly). You can then deduct half of the total SE tax from your gross income when computing federal income tax.
Quarterly Estimated Payments
If you expect to owe $1,000 or more in tax, the IRS requires you to pay in four equal installments throughout the year using Form 1040-ES. This calculator divides your total estimated tax by four to give you each payment amount. You can pay online at IRS Direct Pay, by check, or through the IRS2Go app. Missing or underpaying these deadlines results in an underpayment penalty, typically a few percent of the underpaid amount.
Frequently Asked Questions
What is self-employment tax?
Self-employment tax is the Social Security and Medicare tax paid by freelancers and independent contractors. It is 15.3% of 92.35% of your net self-employment income — 12.4% for Social Security (up to the wage base) and 2.9% for Medicare. Employees split this with employers, but self-employed individuals pay the full amount themselves.
Why is only 92.35% of income subject to SE tax?
The IRS lets you multiply your net earnings by 92.35% (which is 100% minus 7.65%) before calculating the SE tax. This adjustment is equivalent to the employer-side deduction employees receive. It ensures self-employed people are taxed on roughly the same base as employees, accounting for the fact that employers pay half the payroll tax for their workers.
Can I deduct half of my self-employment tax?
Yes. The IRS allows you to deduct exactly half of your SE tax from your gross income when calculating your federal income tax. This deduction appears on Schedule 1 of Form 1040 and reduces your adjusted gross income, which in turn lowers your income tax bill. This calculator accounts for this deduction automatically in its income tax estimate.
How do I pay quarterly estimated taxes?
If you expect to owe at least $1,000 in tax for the year, the IRS requires quarterly estimated tax payments. The due dates are typically April 15, June 15, September 15, and January 15 of the following year. You can pay online at IRS Direct Pay (irs.gov/payments) using Form 1040-ES. This calculator divides your estimated total tax by four to give you each quarterly payment amount.
What is the Social Security wage base for 2025?
For 2025, the Social Security wage base is $176,100. This means the 12.4% Social Security portion of SE tax only applies to the first $176,100 of your combined wages and self-employment income. Earnings above this threshold are still subject to the 2.9% Medicare tax — and an additional 0.9% Additional Medicare Tax if your income exceeds $200,000 (single) or $250,000 (married filing jointly).
Is this calculator accurate for my tax situation?
This calculator provides a solid estimate using 2025 federal tax brackets and SE tax rules. However, it does not account for state income taxes, self-employed health insurance deductions, retirement plan contributions (SEP-IRA, Solo 401k), credits, or other deductions specific to your situation. Always consult a CPA or enrolled agent for advice tailored to your circumstances.
Is my income data private?
Absolutely. All calculations run entirely in your browser using JavaScript. No income figures or personal data are ever sent to any server or stored anywhere. You can disconnect from the internet and the calculator will still work perfectly. Your financial information stays completely private on your device.
What business expenses can I deduct as a freelancer?
Common deductible business expenses include home office costs, business-use vehicle mileage, software and subscriptions, professional development, business insurance, marketing and advertising, and equipment like computers or cameras. These deductions reduce your net self-employment income, which lowers both your SE tax and your income tax. Enter your estimated deductions in the Business Deductions field above.