Self-employment tax calculator.
2026 brackets, all 50 states.

How this is calculated

The math, in plain English.

The numbers above are estimates only. We use the widely-published 2026 brackets and rates; your actual tax owed depends on deductions, credits, and items we don’t ask about (dependents, HSA contributions, SEP-IRA, QBI phaseouts above $191,950 single / $383,900 married). Talk to a CPA before you write the IRS a check this size.

• Self-employment tax — 15.3% of 92.35% of your net business income, split between Social Security (12.4% up to the $168,600 wage base) and Medicare (2.9% on all earnings, plus an additional 0.9% above $200K single / $250K married).
• Half of SE tax is deductible against your federal income tax. We back it out before applying the federal brackets.
• QBI deduction — up to 20% of qualified business income for pass-through structures (sole prop, single-member LLC, partnership). We apply the simple version below the income phaseouts.
• Federal income tax — 2026 ordinary brackets, standard deduction applied ($15K single / $30K married).
• State income tax — flat or progressive rates per state, applied to net income (most states use federal AGI or close to it as the starting point).
• Quarterly estimated payment — total expected tax divided by 4. Safe-harbor is 100% of prior-year tax (110% if AGI > $150K).