How this works
This calculator estimates the US federal income tax owed on a given annual income, using the 2024 IRS bracket structure. It applies the standard deduction for your filing status, then walks the marginal brackets to compute the federal liability. Because state tax varies wildly (zero in Texas, 13% top rate in California), the state field accepts any flat rate so you can plug in your own. Result includes federal tax, state tax, total tax, effective rate, and take-home pay. US-only — for other countries you'll need a country-specific tool.
The formula
2024 standard deductions: $14,600 single, $29,200 married joint, $21,900 head of household. Brackets per IRS Rev. Proc. 2023-34. Excludes Social Security, Medicare (FICA — 7.65% combined for employees), local taxes, and credits like EITC or Child Tax Credit. For an exact figure use a CPA or full tax-prep software like TurboTax / FreeTaxUSA.
Example calculation
- Single filer, $80,000 gross income, 5% state tax (US average).
- Taxable income = 80,000 − 14,600 = 65,400. Federal tax ≈ $9,506 (10%/12%/22% brackets applied).
- State tax = 65,400 × 5% ≈ $3,270. Total ≈ $12,776 → effective rate ~16%, take-home ≈ $67,224.
Frequently asked questions
Why is the effective rate lower than my marginal bracket?
The marginal rate (your highest bracket) only applies to income above that bracket's threshold. Income below it is taxed at lower rates. So someone in the 22% bracket with $80k taxable income pays 10% on the first $11,600, 12% on the next slice, and 22% only on what's above $47,150. Effective rate is the weighted average — always lower than the marginal rate (unless you only earn within the lowest bracket).
Should I itemise instead of taking the standard deduction?
Only if your itemised deductions exceed the standard ($14,600 single / $29,200 joint in 2024). The most common itemised items are mortgage interest, state and local taxes (capped at $10k under SALT), and large charitable donations. After the 2017 tax law roughly doubled the standard deduction, only ~10% of US filers itemise.
What about Social Security and Medicare?
They're separate from federal income tax — collectively called FICA. As an employee you pay 6.2% Social Security on the first $168,600 (2024 cap) and 1.45% Medicare on all wages, plus an extra 0.9% Medicare on income above $200k. Self-employed people pay the full 15.3%. This calculator covers income tax only; subtract another ~7.65% from gross to get a fuller take-home estimate.
Why is this US-only? Can you add other countries?
Tax codes are a country-by-country thing — German tax includes Solidaritätszuschlag and Kirchensteuer, French has CSG and prélèvement à la source bands, Japan layers national, prefectural and municipal residency tax. Each is a separate calculator we'd like to build but haven't yet. For now, the Income Tax Calculator is US federal + US state-average. Other countries are on the roadmap.