How this calculator works
This self-employed tax calculator estimates 2025 total tax on net self-employment income, optionally combined with W-2 wages. It computes self-employment tax (Social Security and Medicare on 92.35% of net SE income), then estimates federal income tax after the deduction for half of SE tax and the standard deduction. A simplified state income tax applies an approximate rate by state.
Social Security on self-employment earnings is 12.4% up to the remaining 2025 wage base ($176,100 minus W-2 wages already subject to Social Security). Medicare is 2.9% on all covered self-employment earnings. Federal income tax uses 2025 brackets on taxable income after pre-tax 401(k) deferrals and up to $2,000 child tax credit per dependent entered.
Total tax is split into recommended quarterly payments. Enter estimated payments already made to see remaining tax due. Effective rate shows total tax as a percentage of combined gross income.
This tool does not model every business deduction, QBI deduction, ACA subsidies, or local taxes. Use it for quarterly planning, then confirm with tax software or a preparer.
What affects the result
- Net self-employment income — Schedule C profit drives both SE tax and income tax. Higher net income increases all components.
- W-2 wages — Combined wages reduce Social Security tax on self-employment income once the wage base is reached and add to federal taxable income.
- Filing status — Standard deduction and bracket thresholds differ for single, married, and head of household filers in 2025.
- Pre-tax 401(k) — W-2 traditional 401(k) contributions lower adjusted gross income and federal tax in this model.
- Dependents — Each dependent entered reduces federal income tax by up to $2,000 in simplified form.
- State selection — Zero-tax states show $0; progressive states may owe more or less than the effective estimate used here.
- Quarterly payments already made — Reduces remaining balance due but does not change total estimated liability.
When to use this calculator
Use this calculator when you start freelancing, receive 1099 income, or need a quarterly estimated tax target for the IRS. It helps compare self-employment tax burden to W-2 employment where the employer pays half of FICA.
Pair with the 401(k) contribution calculator if you also defer W-2 wages, and the income tax estimator for wage-only scenarios. Read the self-employed taxes explained guide for deadlines and safe-harbor rules.
FAQ supplement
Is self-employment tax the same as income tax? No. SE tax is Social Security and Medicare on self-employment earnings. You still owe federal and usually state income tax on net profit.
Do I pay quarterly if I also have a W-2 job? Often yes, if withholding from your job does not cover tax on 1099 income. This calculator shows total liability minus payments already made.
What about business expenses? Enter net self-employment income after expenses. The calculator does not itemize deductions beyond standard or entered 401(k) deferrals.
Related calculators
Compare W-2 take-home pay with the paycheck / take-home pay calculator. Estimate wage-only federal and state tax with the income tax estimator. Model employer match and deferrals with the 401(k) contribution calculator.
FAQ
What is self-employment tax?
Self-employment tax covers Social Security and Medicare for self-employed earners. It is roughly 15.3% on 92.35% of net self-employment income—12.4% for Social Security up to the wage base and 2.9% for Medicare on all covered earnings.
How does W-2 wage income interact with self-employment tax?
Social Security tax applies only up to the 2025 wage base of $176,100 combined across W-2 and self-employment income. W-2 wages count toward that cap first, reducing Social Security tax on self-employment earnings.
What is the SE tax deduction?
You can deduct half of self-employment tax from income when calculating federal income tax. This calculator applies that deduction before estimating federal income tax on combined W-2 and self-employment income.
Does this include quarterly estimated payments?
Yes. Total estimated tax is divided by four to suggest quarterly payment amounts. Enter payments already made to see remaining tax due for planning.
Are pre-tax 401(k) contributions included?
Traditional 401(k) deferrals from W-2 wages reduce adjusted gross income in this model. Solo 401(k) or SEP contributions from self-employment income are not fully modeled—verify limits with a tax professional.
How is state tax estimated?
State tax uses an approximate effective rate by state on adjusted gross income. Real state returns may use progressive brackets, local taxes, and different rules for business income.
Which tax year does this use?
Federal brackets, standard deductions, wage base, and child tax credit reflect 2025 amounts. Tax law can change; verify before filing or making estimated payments.
Who should use this calculator?
Freelancers, consultants, gig workers, and sole proprietors with Schedule C income benefit most. It is a planning estimate—not a substitute for tax software or a preparer when deductions are complex.