About this tool
Income Tax Calculator (custom brackets) is a free, in-browser tool that computes progressive income tax from a bracket table you define — one line per bracket as a lower threshold and the rate applied above it. It reports total tax, after-tax income, your effective rate and your marginal rate, plus a bracket-by-bracket breakdown table.
Each slice of income is taxed at its own bracket's rate: tax = Σ rate_i × (min(income, next threshold) − threshold), so moving into a higher bracket only taxes the income above the threshold — never your whole salary. The effective rate is total tax ÷ income; the marginal rate is the bracket your last unit of income falls in.
Paste the current table for any country, state or tax regime (old vs new slabs, single vs married schedules) and compare scenarios instantly. All computation happens locally in your browser.
Frequently asked questions
What format do the brackets use?
One line per bracket: the lower income threshold and the rate percent, separated by a space — "44725 22" means income above 44,725 (up to the next line's threshold) is taxed at 22%.
What is the difference between effective and marginal rate?
The marginal rate is the bracket rate on your next unit of income; the effective rate is total tax divided by total income, which is always lower under a progressive schedule because earlier slices were taxed at lower rates.
Does entering a higher bracket tax all my income at that rate?
No — that is the most common tax myth. Only the portion of income above each threshold is taxed at that bracket's rate, as the breakdown table makes explicit slice by slice.
Can I model deductions or allowances?
Yes — either subtract them from the income you enter, or add an initial 0%-rate bracket (e.g. "0 0" then "12000 10") to represent a tax-free allowance.
More tools