Income Tax Calculator

How to use this calculator

Select your filing status — single, married filing jointly, married filing separately, or head of household — then enter your annual gross income. The calculator subtracts the standard deduction for your status, runs the remaining taxable income through the federal brackets, and returns your estimated tax bill, effective rate, and marginal bracket.

The result is a starting-point estimate. It does not account for above-the-line deductions like traditional IRA or student loan interest, tax credits, or alternative minimum tax. Think of it as the baseline from which your actual return might improve.

How federal income tax works

The United States taxes income on a progressive bracket system. Rather than taxing all of your income at a single flat rate, the IRS divides your taxable income into bands, each with its own rate. You only pay a higher rate on the dollars that fall within that higher band — not on everything you earned.

Here is a simplified illustration of how the bands work. Suppose the first $11,000 of taxable income is taxed at 10%, the next slice up to $44,000 at 12%, the slice above that at 22%, and so on. A person with $50,000 of taxable income pays 10% on the first $11,000, 12% on the middle portion, and 22% only on the last few thousand dollars — not 22% on the full $50,000. The specific thresholds are adjusted by the IRS each year for inflation; the IRS website always carries the current figures.

Your filing status shapes those thresholds significantly. Married couples filing jointly typically receive bracket thresholds and a standard deduction roughly double those available to single filers, which reduces the effective rate on the same household income.

The standard deduction

Before bracket math even begins, you subtract the standard deduction from gross income. This is a flat amount the IRS allows every filer without requiring receipts or documentation. The alternative — itemizing deductions — requires tallying up expenses like mortgage interest, charitable contributions, and state and local taxes, and is only worth it if that total exceeds the standard deduction. The vast majority of filers take the standard deduction. The amount is adjusted for inflation annually, so check IRS.gov for the current figure for your filing year and status.

Worked example

Imagine a single filer with $75,000 in gross wages. After subtracting the standard deduction, their taxable income is reduced substantially. The calculator then applies each bracket in sequence:

• The first slice of taxable income is taxed at the lowest rate (10%).
• The next slice is taxed at 12%.
• The remaining amount — the portion that spills into the 22% bracket — is taxed at 22%.

Adding those slices together produces the total estimated federal tax. Dividing that total by the original $75,000 gross income gives an effective rate well below 22% — because most of the income was taxed at lower rates. The marginal rate is still 22%, because that is where the last dollar landed.

How to interpret your result

The calculator shows three things: your estimated federal tax, your effective rate, and your marginal bracket.

• Effective rate is the percentage of your total gross income going to federal tax. This is what most people mean when they casually say "my tax rate."
• Marginal rate is the bracket your highest dollar hit. It is important for decisions at the margin — for example, whether a Roth or traditional 401(k) contribution makes more sense.
• Tax owed is an estimate before credits. Tax credits (child tax credit, earned income credit, education credits) reduce this dollar-for-dollar, so your actual bill may be lower.

Common mistakes to avoid

• Thinking all income is taxed at the top rate. Only the dollars in each bracket are taxed at that rate. Moving into a higher bracket does not mean your whole paycheck is suddenly taxed more.
• Confusing gross income with taxable income. Tax is calculated on income after deductions, not on the full amount you earned. Always subtract the standard deduction (or itemized deductions) first.
• Forgetting that this is federal only. Most states have their own income tax on top of the federal bill. Your full tax burden is higher than this estimate if you live in a state with income tax.
• Ignoring tax credits. The calculator does not model credits. If you have qualifying children, paid education expenses, or have low-to-moderate income, available credits could reduce your actual tax owed significantly below this estimate.
• Using this as a substitute for professional advice. Complex situations — self-employment, rental income, capital gains, multiple jobs — can change your liability considerably. A tax professional or the IRS Free File program can give you a more precise figure.

The formula

Taxable income = Gross income − Standard deduction

Federal tax = Σ (taxable income in each bracket × that bracket's rate)

Effective rate = Federal tax ÷ Gross income

A simplified federal estimate, not tax advice. State tax, FICA, and credits are excluded.