How income tax works: brackets, effective vs marginal
The biggest tax myth is that earning more can leave you worse off. It can’t — brackets are marginal. Here’s how progressive tax, the standard deduction, and your effective rate really work.
Brackets are marginal
Each slice of income is taxed at its own rate — only the dollars inside a bracket pay that bracket’s rate. Crossing into a higher bracket never lowers your take-home; just the next dollars are taxed a bit more. The Income Tax calculator applies the 2025 brackets for you.
Effective vs marginal rate
Your marginal rate is the bracket your last dollar falls in. Your effective rate is total tax ÷ total income — always lower, because earlier brackets are taxed less. People quote marginal but feel effective.
The standard deduction ($15k single / $30k married in 2025) is subtracted before brackets apply, so the first chunk of income is effectively tax-free.
Frequently asked questions
- Can a raise put me in a higher bracket and lower my pay?
- No. Only the income above the threshold is taxed at the higher rate, so your take-home always rises with a raise.
- What is the difference between effective and marginal tax rates?
- Marginal is the rate on your last dollar of income; effective is your total tax divided by total income, which is always lower.
- Is take-home pay just income after income tax?
- Not quite — payroll taxes (FICA), state tax, and pre-tax deductions also come out. The [Paycheck calculator](/calculators/paycheck-calculator) estimates the full net pay.
Run your own numbers
Put this guide into practice — these calculators run free in your browser.