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Federal Income Tax Calculator

Tax

Calculate US federal income tax for tax year 2026 or 2025 — effective rate, marginal bracket and taxable income by filing status and deduction type.

Written by · Reviewed by the thecalcu.com team · Last updated October 16, 2026

🇺🇸This tool is specific to United States
$0$1,000,000
$5,000
$0

Federal Tax Owed

$0
Effective Rate
0.00%
tax ÷ gross income — your real overall rate
Marginal Rate
0.00%
the rate on your last dollar earned
Taxable Income
$0

What is a Federal Tax?

The Federal Income Tax Calculator works out how much US federal income tax you owe on your wages for a given tax year. You enter gross income, filing status, pre-tax deductions, and whether you take the standard deduction or itemize. It returns the tax owed, your taxable income, your effective rate, and the marginal bracket your last dollar lands in.

The US system is progressive. Each slice of taxable income is taxed at the rate for its own bracket, so a bigger paycheck raises your tax without ever lowering your take-home pay. The calculator applies that bracket math using the figures the IRS published for tax years 2026 and 2025, so you can see this year's picture or the return you're finishing. It estimates liability only. It doesn't know what your employer withheld, which is what the Tax Refund Estimator adds on top.

Show formula & methodology ↓Hide formula & methodology ↑

Formula & Methodology

The calculation runs in three steps.

Step 1, adjusted gross income: AGI = gross income − pre-tax deductions (traditional 401(k), HSA, pre-tax premiums).

Step 2, taxable income: taxable income = AGI − the larger of your standard or itemized deduction. Standard deductions are $16,100 (single and married filing separately), $24,150 (head of household), and $32,200 (married filing jointly) for 2026, and $15,750, $23,625, and $31,500 for 2025.

Step 3, apply the brackets: tax = Σ (rate × income inside each bracket). Here are the 2026 brackets for the two most common filing statuses.

Rate Single, taxable income up to Married filing jointly, up to
10% $12,400 $24,800
12% $50,400 $100,800
22% $105,700 $211,400
24% $201,775 $403,550
32% $256,225 $512,450
35% $640,600 $768,700
37% over $640,600 over $768,700

For 2025 a single filer's 10% bracket ends at $11,925, 12% at $48,475, 22% at $103,350, 24% at $197,300, 32% at $250,525, and 35% at $626,350.

Worked example (single filer, 2026): gross income $85,000 with $5,000 going into a traditional 401(k).

  • AGI: $85,000 − $5,000 = $80,000
  • Standard deduction: $16,100, so taxable income is $63,900
  • Tax: $12,400 × 10% + ($50,400 − $12,400) × 12% + ($63,900 − $50,400) × 22% = $1,240 + $4,560 + $2,970 = $8,770
  • Effective rate: $8,770 ÷ $85,000 = 10.3%, marginal rate 22%

Run the same inputs with the 2025 tax year selected and you get $9,049, because the 2025 brackets are narrower and the standard deduction is $350 smaller.

How to use this Federal Tax calculator

  1. Pick the Tax Year. The calculator defaults to 2026. Choose 2025 if you're working on a return you haven't finished yet.
  2. Enter your Gross Income for the year, before any deductions.
  3. Select your Filing Status: Single, Married Filing Jointly, Married Filing Separately, or Head of Household.
  4. Type your Pre-Tax Deductions, the combined traditional 401(k), HSA, and pre-tax premium amounts for the year.
  5. Choose your Deduction Type. Standard applies the amount for your filing status. Choose Itemized if your deductible expenses are larger.
  6. If you chose Itemized, fill in Itemized Deductions with the total.
  7. Read the Federal Tax Owed card, then check the effective and marginal rates and taxable income. Open the step breakdown to see how each number was built, and change pre-tax deductions to see how much a retirement contribution would save.

Common Mistakes to Avoid

  • Entering take-home pay. The gross income field wants your pay before taxes and deductions. Using a net figure understates your tax.
  • Counting the 401(k) twice. If your W-2 wages already exclude your pre-tax 401(k), don't subtract it again in the pre-tax field. Use gross pay and enter the contribution once.
  • Reading the marginal rate as your tax rate. A 22% bracket doesn't mean 22% of your income goes to the IRS. Your effective rate is the one that describes your total bill.
  • Comparing the wrong tax year. Brackets and standard deductions change every year. Check the Tax Year field before you compare numbers with a pay stub or a prior return.
  • Treating the result as a balance due. This is your total liability. Whether you owe more or get a refund depends on withholding and credits, so run the W-4 Withholding Calculator if you want to adjust your paycheck.
  • Forgetting income the calculator doesn't model. Self-employment income carries its own tax, and investment gains can use different rates. Check the Self-Employment Tax Calculator if you earn freelance income.

What the Results Tell You

Federal Tax Owed is your total federal income tax liability for the year on the income you entered. It's the number to compare against your total withholding.

Taxable Income is what's left after pre-tax deductions and your deduction choice. It's the figure the brackets apply to, and it's lower than your salary, sometimes by a lot.

Effective Tax Rate divides the tax owed by your gross income. It shows what share of your pay goes to federal income tax overall, and it tends to sit well below the bracket you're in.

Marginal Tax Rate is the rate on your next dollar of taxable income. It tells you what a raise, bonus, or extra retirement contribution is worth after tax. If you're at 22% and put another $1,000 into a traditional 401(k), you save about $220 in federal tax this year.

Quick Reference

Item 2026 2025
Standard deduction, single $16,100 $15,750
Standard deduction, married filing jointly $32,200 $31,500
Standard deduction, head of household $24,150 $23,625
Employee 401(k) contribution limit $24,500 $23,500
Child tax credit (per child, not modeled here) $2,200 $2,200

Related tools: the Tax Refund Estimator turns your liability into a refund or balance due, the Payroll Tax Calculator covers Social Security and Medicare, and the 401(k) Contribution Calculator shows how contributions change your taxable income.

Authoritative references

Frequently Asked Questions

What does the Federal Income Tax Calculator tell me?

It estimates how much federal income tax you owe on wages for a single tax year, along with your taxable income, effective rate, and marginal bracket. You pick the tax year (2026 or 2025), your filing status, any pre-tax deductions, and either the standard or an itemized deduction. It's an estimate of liability, so it doesn't know how much was withheld from your pay.

What are the 2026 federal income tax brackets?

The seven rates stay at 10%, 12%, 22%, 24%, 32%, 35%, and 37%, but the dollar thresholds moved up. For a single filer in 2026, the 10% rate covers taxable income up to $12,400, 12% runs to $50,400, 22% to $105,700, 24% to $201,775, 32% to $256,225, and 35% to $640,600. Anything above $640,600 is taxed at 37%. Married couples filing jointly get roughly double those ranges.

What is the standard deduction for 2026?

It's $16,100 for single filers and married people filing separately, $24,150 for heads of household, and $32,200 for married couples filing jointly. For 2025 the amounts were $15,750, $23,625, and $31,500. People 65 or older, or blind, add $1,650 per condition for 2026 ($2,050 if unmarried), though this calculator doesn't add that automatically, so use the itemized field if you want to include it.

What's the difference between my marginal rate and my effective rate?

Your marginal rate is the rate on your last dollar of taxable income. Your effective rate is total tax divided by gross income, which is always lower because the standard deduction and the lower brackets shelter most of what you earn. A single filer earning $85,000 in 2026 is in the 22% bracket but pays under 12% of their gross income in federal income tax.

Does a raise push all my income into a higher bracket?

No. Only the dollars above a bracket threshold are taxed at the higher rate, and everything below stays at the earlier rates. Crossing from the 22% to the 24% bracket means the extra income is taxed at 24%, not that your whole salary jumps to 24%. A raise can never leave you with less take-home pay than before because of brackets alone.

Should I take the standard deduction or itemize?

Itemize only if your deductible expenses add up to more than the standard deduction for your filing status, which is $16,100 for a single filer in 2026. Mortgage interest, state and local taxes (within the cap), and charitable gifts are the usual items. Most households with moderate incomes come out ahead with the standard deduction, and it takes no record-keeping.

What counts as a pre-tax deduction?

These are amounts that come off your income before the tax calculation, such as traditional 401(k) or 403(b) contributions, health savings account deposits, and pre-tax health insurance premiums. The employee 401(k) limit is $24,500 for 2026 and was $23,500 for 2025. Add them together in the pre-tax deductions field, and use the [401(k) Contribution Calculator](/us/401k-contribution-calculator/) if you're deciding how much to put in.

Can I use this to calculate my 2025 taxes?

Yes, choose 2025 in the Tax Year field. It applies the 2025 brackets and standard deduction, which is useful if you're filing late, on extension, or amending, or just comparing your 2025 bill with what 2026 looks like. The default is 2026.

Why doesn't my result match my actual tax return?

The calculator covers ordinary income tax on one gross income figure. A real return also reflects tax credits, self-employment tax, capital gains rates, the alternative minimum tax, the net investment income tax, and deductions it doesn't model. For a refund or balance-due estimate that includes credits and withholding, use the [Tax Refund Estimator](/us/tax-refund-estimator/).

Does it include Social Security, Medicare, or state tax?

It leaves all three out. Social Security and Medicare (FICA) payroll tax comes out of your paycheck separately at 7.65% for most employees, and states set their own income tax rules. The [Payroll Tax Calculator](/us/payroll-tax-calculator/) covers the payroll side.

How does filing status change the result?

Filing status sets both the standard deduction and where each bracket starts. Married filing jointly has the widest brackets, head of household sits between joint and single, and married filing separately matches single until the top, where the 35% bracket ends sooner. The same income can produce a noticeably different bill under each status, so check the one you're eligible for.

Does it apply the child tax credit?

No, the calculator doesn't include credits at all. The child tax credit is $2,200 per qualifying child for 2026, and it comes off your tax bill dollar for dollar, so it can change the result a lot for families. The Tax Refund Estimator has a credits field where you can enter it.

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