Percentage calculator

How it works

How it works

The calculator has three tabs for the three most common percentage questions:

• X% of Y: how much a percentage of a number is (X / 100 × Y). 21% of 200 is 42. You also get Y with that percentage added and taken off, handy for markups and discounts: 200 + 21% = 242 and 200 − 21% = 158.
• What %: what percentage an amount is of a total (X / Y × 100). 42 is 21% of 200.
• Change: how much a value went up or down, as a percentage ((B − A) / |A| × 100). From 50 to 75 is a 50% increase; from 80 to 60, a 25% decrease.

Details

You can type a decimal point or a comma and a thousands separator. Results show up to 4 decimals. There is no percentage change from 0 (any change would be infinite), so in that case the tool explains it instead of giving a number.

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