Percentage calculator
Percent of a number, percent change, increases, discounts and the original value.
How to use it
- Find the question that matches yours. Each box answers a different everyday percentage question.
- Type your numbers into the sentence. Answers update as you type, and you can use commas, like 1,250.
- Check the formula under each answer to see how it was worked out.
- Click Copy to copy an answer.
Questions
How do I calculate a percentage of a number?
Divide the percentage by 100 and multiply by the number. For example, 15% of 200 is 15 ÷ 100 × 200 = 30.
How do I calculate percentage change?
Subtract the old value from the new one, divide by the old value, then multiply by 100. Going from 80 to 100 is (100 − 80) ÷ 80 × 100 = a 25% increase.
Is a change from 10% to 12% a 2% increase?
It's an increase of 2 percentage points, but a 20% increase in relative terms, because 2 is 20% of 10. News reports often mix these up.
How do I find the price before a discount?
Divide the sale price by what's left after the discount. Something that costs 80 after 20% off cost 80 ÷ 0.8 = 100. Use the last box: 80 is 80% of what number?