How US Federal Income Tax Is Calculated
Federal income tax is progressive: you pay lower rates on the first portion of taxable income and higher rates on amounts above each threshold. Your taxable income is total income minus deductions (standard or itemized). Tax credits reduce your tax bill dollar-for-dollar after applying the rate schedule.
2026 Federal Tax Brackets (Single Filer)
| Taxable Income | Rate |
|---|---|
| Up to $11,925 | 10% |
| $11,925 โ $48,475 | 12% |
| $48,475 โ $103,350 | 22% |
| $103,350 โ $197,300 | 24% |
| $197,300 โ $250,525 | 32% |
| $250,525 โ $626,350 | 35% |
| Over $626,350 | 37% |
This calculator covers federal income tax only. FICA taxes (Social Security 6.2%, Medicare 1.45%), state income taxes, and the net investment income surtax are not included. For a full picture, use the IRS Tax Withholding Estimator.
Frequently Asked Questions
The marginal rate is the rate applied to your last dollar of income. The effective rate is total tax divided by total income โ always lower than the marginal rate for progressive tax systems.
Itemize if your qualifying expenses (mortgage interest, state taxes, charitable donations, etc.) exceed the standard deduction ($15,000 single / $30,000 MFJ in 2026). Most filers benefit from the standard deduction.