Percentage Calculator
Six handy percentage calculators — pick the one you need
Given final value after a % increase or decrease, find the original.
Symmetric difference — neither value is treated as the "original".
Frequently Asked Questions
About This Percentage Calculator
This free Percentage Calculator covers six common percentage problems — all calculated instantly in your browser. Whether you need to find a percentage of a number, calculate how much prices changed, reverse-calculate an original value, or compare two numbers, this tool has you covered.
| Calculator | Formula | Example |
|---|---|---|
| X% of Y | (X / 100) × Y | 20% of 500 = 100 |
| X is what % of Y | (X / Y) × 100 | 80 is 40% of 200 |
| % Change | ((New − Old) / Old) × 100 | 100→150 = +50% |
| Add % | N × (1 + P/100) | 1000 + 18% = 1180 |
| Remove % | N × (1 − P/100) | 1180 − 18% ≈ 967.6 |
| Reverse % | Final / (1 ± P/100) | 1180 after +18% → orig = 1000 |
| % Difference | |A−B| / ((A+B)/2) × 100 | |80−120| / 100 × 100 = 40% |
Standards & References
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