Percentage Calculator
Work out percentages three ways: find a percent of a number, see what percent one number is of another, or measure the percentage change between two values. Results update as you type.
How to use the percentage calculator
- Pick a mode: percent of a number, what percent X is of Y, or percentage change.
- Type the two values into the labeled inputs.
- Read the result instantly, no need to press calculate.
Examples
What is 20% of 250?
Mode: % of a number, percentage 20, value 250
50
Price change from 100 to 150
Mode: % change, from 100, to 150
+50%
Frequently asked questions
How do I find a percentage of a number?
Multiply the number by the percent and divide by 100. For example, 20% of 250 is 250 x 20 / 100 = 50. The 'percent of a number' mode does this for you.
How do I calculate a percentage increase or decrease?
Subtract the old value from the new value, divide by the old value, then multiply by 100. Going from 100 to 150 is a 50% increase; 100 to 50 is a 50% decrease. Use the 'percentage change' mode.
How do I work out what percent one number is of another?
Divide the part by the whole and multiply by 100. For example, 50 out of 200 is 50 / 200 x 100 = 25%. The 'X is what % of Y' mode handles this.
What is the difference between percentage points and percent?
Percentage points measure the simple gap between two percentages, while percent change measures the relative change. Moving from 10% to 12% is a rise of 2 percentage points but a 20% increase.
What happens if a value is zero?
Dividing by zero has no meaningful percentage, so the calculator returns 0 when the whole or the starting value is zero rather than showing an error.
Is my data sent anywhere?
No. Every calculation runs in your browser, so the numbers you enter never leave your device.
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