Estimate your federal income tax using official 2026 IRS brackets and deductions.
Taxable income: the number that actually matters
Federal brackets apply to taxable income — gross income minus the standard deduction ($16,100 single, $32,200 joint, $24,150 head of household in 2026) or itemized deductions. A single earner making $100,000 is taxed on only $83,900.
Marginal vs. effective tax rate
Your marginal rate is the tax on your last dollar (22% in the $100,000 example); your effective rate is total tax ÷ total income (13.17%). Only dollars above each threshold are taxed at the higher rate — never your entire income.
Standard deduction in 2026
About 90% of taxpayers take the standard deduction. Itemizing only wins if mortgage interest, state/local taxes (capped at $10,000), and charitable gifts exceed the standard amount.
What is the difference between marginal and effective tax rate?
Marginal is the rate on your next dollar; effective is total tax divided by total income. Your effective rate is always lower than your marginal rate.
Should I take the standard deduction or itemize?
Take whichever is larger. For 2026, itemizing only wins if deductions exceed $16,100 single / $32,200 joint / $24,150 head of household.
Does this include state income tax?
No — federal income tax only. State rates range from 0% to over 13%.
What changed for 2026 vs. 2025?
Bracket thresholds, the standard deduction, and the Social Security wage base were adjusted upward for inflation. The 10%–37% structure is unchanged.
Is this tax advice?
No. This is an educational estimate using published IRS figures. Consult a qualified tax professional for major decisions.
How to use this calculator
Three inputs produce the full estimate. The calculator handles the bracket layering automatically — you never need to look up a tax table.
- Gross annual income. Your total earnings before any deductions: salary, bonuses, freelance and business income combined. Enter the full-year figure, not per-paycheck.
- Filing status. Single, married filing jointly, or head of household. This single choice changes everything downstream: the standard deduction ($16,100 single, $32,200 joint, $24,150 head of household for 2026), the bracket thresholds, and therefore the final bill. Married couples should model both “joint” and two “single” scenarios when deciding how to file.
- Deduction type. Leave it on “Standard (automatic)” for the quick estimate, or switch to “Itemized” and enter your total itemized deductions (mortgage interest, state and local taxes up to the cap, charitable gifts). Itemizing only wins when your deductions beat the standard amount for your status.
The calculator first subtracts your deduction to reach taxable income — the only number the brackets actually touch. It then applies the 10%–37% brackets in layers (each rate taxes only the dollars inside its band), and reports both your marginal and effective rates. If the result shows you are significantly over- or under-withheld versus your employer’s payroll deductions, use it as the basis for filing a new W-4 — adjusting withholding during the year beats waiting for a refund or a bill in April.
Understanding your results
- Taxable income. Gross income minus your deduction (standard or itemized). This is the figure that determines your bracket placement — a $100,000 single earner taking the standard deduction is taxed on only $83,900.
- Federal income tax. The estimated total liability for the year, computed layer by layer through the brackets.
- Marginal tax rate. The rate on your next dollar of income — the number that matters for decisions like “should I do overtime?” or “is this deduction worth it?”
- Effective tax rate. Total tax divided by gross income. Because of the layered brackets, this is always lower than your marginal rate — 13.17% versus 22% in the $100,000 example below — and it is the honest measure of your overall burden.
- After-tax income. Gross minus federal tax: the starting point for your real budget before state tax and payroll taxes.
Worked example
A single filer earning $100,000 in 2026, taking the standard deduction:
- Standard deduction: $16,100 → taxable income: $83,900
- Marginal rate: 22% (the rate on the last dollar earned)
- Federal income tax: $13,170 (computed through the bracket layers)
- Effective rate: $13,170 ÷ $100,000 = 13.17%
- After federal tax: $86,830 — before state tax and FICA
Notice the gap between the 22% marginal and 13.17% effective rates: only the dollars above each threshold are taxed at the higher rate. A raise that pushes you “into the 24% bracket” taxes just the extra dollars at 24% — your existing income is untouched.
Frequently asked questions
Do I have to file a return if I earned very little?
Not always — filing thresholds roughly track the standard deduction, so a single filer under about $16,100 of gross income generally owes nothing and may not need to file. But file anyway if you had withholding: it is the only way to claim a refund, and low earners may qualify for refundable credits.
What is the difference between a tax credit and a tax deduction?
A deduction shrinks the income being taxed (a $1,000 deduction saves $220 at the 22% bracket); a credit shrinks the tax bill dollar for dollar (a $1,000 credit saves $1,000). Credits are strictly more valuable — which is why the child tax credit and education credits get so much attention at filing time.
Are Social Security benefits taxed?
They can be. Depending on your “combined income,” up to 85% of benefits become taxable at ordinary rates — which surprises many new retirees. The taxation of benefits is one reason Roth withdrawals (which do not count toward combined income) are so valuable in retirement planning.
How can I legally lower my taxable income?
The big levers: pre-tax 401(k) and HSA contributions, deductible student-loan interest, and — if your itemized total beats the standard deduction — mortgage interest, state and local taxes (capped at $10,000), and charitable gifts. Each dollar shifted out of taxable income saves your marginal rate.
When are 2026 federal taxes due?
April 2027, typically the 15th. Quarterly estimated payments apply if you owe significantly through freelance or investment income — the IRS charges penalties for under-withholding, so adjust W-4 withholding or pay estimates during the year rather than settling up in April.
Does this calculator handle capital gains or rental income?
No — it models ordinary wage-like income through the standard brackets. Long-term capital gains, qualified dividends, and rental income follow separate rate schedules and rules, so treat this estimate as your baseline and consult the dedicated IRS worksheets for investment income.