Four common percentage calculations, with the formula shown for every result.
e.g. 20% of 100 = 20
Result
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Enter both values to see the calculation.
e.g. 20 is what % of 100 = 20%
Result
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Enter both values to see the calculation.
e.g. 100 → 120 = 20% increase
Result
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Enter both values to see the calculation.
e.g. if 20% = 20, then 100% = 100
Then 100% equals
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Enter both values to see the calculation.
Percentages lie by omission. A 50% pay cut followed by a 50% pay raise doesn't get you back to where you started — you're down 25%. A store discount of "40% off, then an extra 20% off" isn't 60% off — it's 52%. This calculator handles the math correctly, but it's worth knowing why stacked percentages don't add up the way they feel like they should: each percentage applies to whatever number came before it, not the original number.
If you're comparing two discounts, two raises, or two changes over time, always calculate them in sequence rather than adding the percentages together.
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