Percentage change calculator
Compare an old and a new value to see how much it went up or down in percent. Useful for price changes, monthly sales, test results and salary offers.
Processed on your deviceHow to calculate percentages
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Pick the question you need: X% of Y, X is what % of Y, percentage change, or add/subtract a percentage.
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Type your numbers. The answer updates instantly.
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Use the result in your homework, budget, discount or report.
Frequently asked questions
What's the percentage change from 80 to 100?
+25%: (100 − 80) ÷ 80 × 100 = 25. Going back from 100 to 80 is −20%, because the base is different.
How do I calculate X% of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 is 150 × 20 ÷ 100 = 30.
How do I work out percentage change?
Subtract the old value from the new one, divide by the old value and multiply by 100. Going from 80 to 100 is (100 − 80) ÷ 80 × 100 = +25%.
Why isn't a 10% rise followed by a 10% fall back to the start?
Because the second percentage applies to a different base. 100 + 10% = 110, and 110 − 10% = 99.