Income Tax Calculator

What This Income Tax Calculator Does

Use this calculator to estimate U.S. federal individual income tax for tax years 2025 and 2026. It applies progressive federal tax brackets, filing status, the standard or an entered itemized deduction, the higher standard deduction for age 65 or blindness, the enhanced senior deduction introduced for 2025–2028, and federal tax credits you enter. State and local income taxes and payroll taxes are not included.

Inputs and What They Mean

Select the tax year and filing status, then enter your annual gross income. Choose the standard deduction or enter an itemized deduction amount. If you use the standard deduction, the calculator can add the IRS higher-standard-deduction amount for age 65 or blindness. For taxpayers age 65 or older, it also models the separate enhanced senior deduction that applies for 2025–2028, subject to its income phaseout. Credits are entered manually because eligibility and credit amounts depend on circumstances that this simplified estimator does not determine.

How U.S. Federal Income Tax Is Calculated

The calculator determines the applicable deduction, subtracts it from the income you enter, and allocates the resulting taxable income across the federal tax brackets. Each bracket rate applies only to the portion of taxable income inside that bracket. Finally, the federal tax credits you enter are subtracted, with estimated tax not allowed to fall below zero.

2026 Federal Tax Rules Used

For 2026, the calculator uses the IRS-published federal rates of 10%, 12%, 22%, 24%, 32%, 35% and 37%, together with the 2026 filing-status thresholds and standard deductions. The standard deduction is $16,100 for single or married filing separately, $24,150 for head of household and $32,200 for married filing jointly. The IRS also provides a separate enhanced senior deduction of up to $6,000 per eligible person for tax years 2025–2028, subject to an income phaseout.

How the Enhanced Senior Deduction Works

The enhanced senior deduction is separate from the higher standard deduction for people age 65 or older. It can be available whether a taxpayer uses the standard deduction or itemizes. The maximum is $6,000 per eligible person, or up to $12,000 for a married couple filing jointly when both spouses qualify. The deduction begins to phase out above $75,000 of modified adjusted gross income for most filers and $150,000 for joint filers. Tervilo uses the income entered in this simplified calculator as a proxy for the IRS MAGI phaseout test, so taxpayers with complex MAGI adjustments should verify the result with IRS instructions or a tax professional.

How to Use the Income Tax Calculator

1. Select the tax year.
2. Select your federal filing status.
3. Enter your annual gross income.
4. Choose the standard deduction or itemized deductions.
5. If applicable, select age 65 or older and/or blindness adjustments.
6. Enter any federal tax credits you want to model.
7. Select Calculate and review the federal tax summary and bracket breakdown.
8. Change one assumption at a time when comparing scenarios.

Effective Tax Rate vs. Marginal Tax Rate

Your effective tax rate is the estimated federal income tax divided by the gross income entered. Your marginal tax rate is the rate applying to the next dollar of taxable income in the current bracket. A taxpayer in a 22% marginal bracket does not pay 22% on every dollar of income because the lower portions are taxed at lower rates.

Important Assumptions and Limitations

This is a planning estimator for U.S. federal individual income tax, not a tax-return preparation engine. It does not calculate state or local income tax, Social Security or Medicare taxes, self-employment tax, alternative minimum tax, net investment income tax, capital-gains-specific rates, detailed qualified business income calculations, eligibility for individual credits, or every deduction and adjustment. It also does not determine every Schedule 1-A deduction, such as qualified tips, overtime or vehicle-loan interest. Itemized deductions and manually entered credits are treated as amounts supplied by the user. The enhanced senior deduction uses gross income as a simplified proxy for the IRS MAGI phaseout test. Verify your circumstances against current IRS guidance before filing or making tax decisions.

Practical Planning Tip

Use the calculator to compare scenarios rather than treating one result as a final tax liability. Try different filing statuses, deduction assumptions and credit amounts, then compare taxable income, effective rate and marginal rate. Tax rules change by year, so confirm the applicable tax year before relying on an estimate.