Federal Income Tax Calculator

Federal Income Tax Calculator

How to Use the Federal Income Tax Calculator

1. 1

   Choose your filing status and enter income

   Pick Single, Married filing jointly or Head of household, then enter gross income from wages and other ordinary income before any pre-tax contributions. Add long-term capital gains and qualified dividends in their own box if you have them.

2. 2

   Enter pre-tax contributions

   Add what you put into a traditional 401(k) or 403(b), an HSA and a deductible traditional IRA for the year. Turn on the age-50 toggle to use the higher catch-up limits. Amounts above the 2026 limit are capped.

3. 3

   Pick your deduction and add children

   Leave the Standard tab selected, or switch to Itemized and enter your Schedule A total. Enter the number of children under 17 for the Child Tax Credit.

4. 4

   Read the results and the bracket table

   Check your AGI, taxable income, tax before credits, credit used, total federal income tax, effective rate and marginal rate. The table below shows how much of your income falls in each bracket and the tax on it.

How federal income tax is calculated

Start with total income, subtract above-the-line adjustments such as traditional 401(k) deferrals, HSA contributions and deductible IRA contributions to get adjusted gross income (AGI), then subtract the standard deduction or your itemized deductions to get taxable income. For 2026 the standard deduction is $16,100 for single filers, $32,200 for married couples filing jointly and $24,150 for heads of household.

Taxable income runs through the brackets: only the dollars inside each band are taxed at that band's rate. Long-term gains and qualified dividends sit on top of ordinary income and are taxed at 0%, 15% or 20% depending on where they land. Credits such as the Child Tax Credit ($2,200 per child, reduced by $50 for each $1,000 of income above $200,000, or $400,000 for joint filers) then come off the tax itself.

AGI = income + long-term gains - 401(k) - HSA - IRA; Taxable income = AGI - deduction; Tax = bracket tax on ordinary income + 0/15/20% on gains stacked on top; Federal income tax = tax - Child Tax Credit (up to the tax)

Worked examples

Single filer earning $85,000 who puts $10,000 into a traditional 401(k), taking the standard deduction:

• AGI: $85,000 - $10,000 = $75,000. Taxable income: $75,000 - $16,100 = $58,900
• 10% on the first $12,400 = $1,240; 12% on the next $38,000 = $4,560; 22% on the last $8,500 = $1,870
• Federal income tax: $7,670. Effective rate 9.0% of $85,000; marginal rate 22%
• Without the 401(k) contribution the tax would be $9,870, so the $10,000 contribution cut the bill by $2,200
• Married couple filing jointly, $150,000 of income, $20,000 to a 401(k), $8,750 to a family HSA and two children under 17: AGI $121,250, taxable income $89,050, tax before credits $10,190, Child Tax Credit $4,400, federal income tax $5,790 (3.9% effective)
• Married couple with $120,000 of wages and $30,000 of long-term gains: taxable income $117,800. Ordinary tax on $87,800 is $10,040; $11,100 of the gains fall in the 0% band and $18,900 in the 15% band ($2,835), for $12,875 in total

2026 federal income tax brackets

Taxable income ranges for each rate (IRS Rev. Proc. 2025-32). Each rate applies only to the income inside its band.

Estimated federal income tax by income

Wage income only, standard deduction, no pre-tax contributions and no credits, calculated with this tool. Effective rate is tax divided by gross income.

Legal ways to lower your federal income tax

Tax avoidance, arranging your affairs to use the rules as written, is legal. Evasion, such as hiding income or claiming expenses you did not have, is not. These are the mainstream, IRS-sanctioned options:

• Contribute to a traditional 401(k), 403(b) or similar plan: up to $24,500 in 2026, plus an $8,000 catch-up if you are 50 or older. Each dollar comes off taxable income at your marginal rate.
• Fund a health savings account if you have a high-deductible health plan: up to $4,400 for self-only coverage or $8,750 for family coverage. Contributions are deductible, growth is untaxed, and withdrawals for medical costs are tax-free.
• Make a deductible traditional IRA contribution: up to $7,500, or $8,600 at 50 and over. The deduction phases out if you or your spouse have a workplace plan and your income is above IRS limits.
• Compare itemizing with the standard deduction. If you are close, bunching two years of charitable gifts into one year (for example through a donor-advised fund) can push you over the standard deduction every other year. The SALT cap is $40,400 for most filers.
• Claim the Schedule 1-A deductions if they apply to you, for 2025 through 2028: qualified tips up to $25,000, qualified overtime pay up to $12,500 ($25,000 joint), interest on a qualifying new-car loan up to $10,000, and $6,000 per person aged 65 or older. They phase out at higher incomes and are not modeled in this calculator.
• Harvest capital losses to offset gains, and hold investments more than a year so gains qualify for the lower long-term rates.

What this calculator does not include

This is a planning estimate of federal income tax. It excludes state and local income tax, Social Security and Medicare, self-employment tax, the 3.8% net investment income tax and the alternative minimum tax. It does not model the Earned Income Tax Credit, education credits, the dependent care credit, the credit for other dependents, the IRA deduction phase-out, the Schedule 1-A deductions, the new non-itemizer charitable deduction, or the earned-income test that limits the refundable part of the Child Tax Credit (Schedule 8812). Married filing separately is not supported. AGI is used in place of modified AGI.

For your actual return, use the IRS Form 1040 instructions or tax software, and consider a CPA or enrolled agent if your situation involves a business, rental property, stock compensation or large one-time income.

Features

• Uses the 2026 tax brackets and standard deduction for single, married filing jointly and head of household
• Subtracts 401(k), HSA and deductible IRA contributions, with the 2026 limits and age-50 catch-up shown
• Standard or itemized deduction, plus the Child Tax Credit with its income phase-out
• Taxes long-term capital gains and qualified dividends at 0%, 15% and 20%, stacked on top of ordinary income
• Shows AGI, taxable income, tax before and after credits, effective and marginal rate
• Bracket-by-bracket table showing how much income falls in each rate

Frequently Asked Questions