Free online 2025-2026 income tax calculator

How to use

1. Enter your gross income and pick a filing status.
2. If you want the full take-home picture, check Add Social Security & Medicare (FICA). Leave it off for just federal income tax.
3. Switch to Extended to add other income, 401(k) contributions, itemized deductions, or a self-employed flag.
4. The breakdown table below the summary cards walks from gross income all the way down to monthly take-home — the same format as the worked example on this page, filled with your numbers.

2025 standard deductions

2025 federal income tax brackets

Each row shows the upper bound of the bracket. You only pay a given rate on income that falls inside that bracket, not on all your income.

Single and married filing separately

Married filing jointly and qualifying surviving spouse

Head of household

Bracket history — what changed 2024 → 2025

Brackets move up with inflation every year. Below is how the single-filer thresholds shifted. The rate structure itself has been stable since 2018 (Tax Cuts and Jobs Act); what changes is the dollar threshold where each rate takes over.

And the standard deduction by year:

For the Social Security wage base, 2024 was $168,600 and 2025 is $176,100. IRS publishes the following year’s figures every October; 2026 numbers will be available in fall 2025 and historically rise another 2-3 %.

How federal tax is calculated

Taxable income = gross income + other income − 401(k) − deduction

Tax is then applied progressively: you pay the bracket rate only on income within that bracket, not on all your income.

Example (single, $75,000 gross, standard deduction):

• Taxable income: $75,000 − $15,000 = $60,000
• 10% on first $11,925 = $1,192.50
• 12% on $11,925 – $48,475 = $4,386
• 22% on $48,475 – $60,000 = $2,535.50
• Federal income tax: $8,114

FICA (2025)

• Social Security: 6.2% on the first $176,100 of earned income (2025 SSA wage base, up from $168,600 in 2024). Wages above this cap are not taxed for Social Security.
• Medicare: 1.45% on all wages, plus an additional 0.9% on wages above $200,000 (single) / $250,000 (married filing jointly).

FICA is opt-in in this calculator — flip the toggle above the form to add it to the total.

Worked example — single filer, $75,000 salary, full breakdown

With the FICA toggle on, here’s the full 2025 picture on a $75,000 salary:

• Effective tax rate: 13,852 / 75,000 = 18.5%
• Marginal rate: 22% (the bracket the next dollar would fall into)

With the FICA toggle off, the same $75,000 shows only $8,114 of federal income tax — a 10.8% effective rate — which is what most people intuitively think of as “my tax”.

Marginal vs. effective rate — why both matter

Marginal rate is the tax on the next dollar you earn. It drives decisions like “should I take overtime?” or “should I max out my 401(k)?”

Effective rate is what you actually pay as a share of your income. It’s always lower than the marginal rate because the progressive bracket structure taxes your earlier dollars at lower rates.

At $75,000 single with standard deduction, you’re in the 22% bracket but pay 10.8% overall (federal) or 18.5% (with FICA). The gap is where tax planning lives — a dollar moved into a 401(k) saves you 22%, not 10.8%.

Notes

• Source: IRS Rev. Proc. 2024-40; IRS IR-2024-273 (October 22, 2024); SSA 2025 Social Security changes fact sheet.
• Not included: state income tax (varies 0–13.3%), AMT, tax credits (child tax credit, EITC), long-term capital gains, qualified dividends, self-employment deductions beyond SE tax. If any of these are a big part of your picture, this number is an undercount or overcount.
• 401(k) reduces taxable income, not FICA — traditional 401(k) contributions come out of your federal taxable income but still count for Social Security and Medicare. The 2025 elective deferral limit is $23,500.
• This tool is for estimation. For filing, use IRS software or a tax professional.