How to use the Percentage Calculator
- Fill in Percentage and Of this number. Type a number or drag the slider.
- The result appears straight away and changes as you type. There is no button to press.
- Use the worked example, table and formula below to check the result or compare other values.
Worked example
20% of 500 is 100. Adding 20% to 500 gives 600, and taking 20% off 500 gives 400.
Quick answers
- What is 5% of 1,000?5% of 1,000 is 50.
- What is 10% of 1,000?10% of 1,000 is 100.
- What is 15% of 1,000?15% of 1,000 is 150.
- What is 20% of 1,000?20% of 1,000 is 200.
- What is 25% of 1,000?25% of 1,000 is 250.
- What is 50% of 1,000?50% of 1,000 is 500.
- What is 75% of 1,000?75% of 1,000 is 750.
Percentage table
Common percentages of round numbers.
| Percentage | of 100 | of 500 | of 1,000 | of 5,000 | of 10,000 |
|---|---|---|---|---|---|
| 5% | 5 | 25 | 50 | 250 | 500 |
| 10% | 10 | 50 | 100 | 500 | 1,000 |
| 15% | 15 | 75 | 150 | 750 | 1,500 |
| 20% | 20 | 100 | 200 | 1,000 | 2,000 |
| 25% | 25 | 125 | 250 | 1,250 | 2,500 |
| 50% | 50 | 250 | 500 | 2,500 | 5,000 |
| 75% | 75 | 375 | 750 | 3,750 | 7,500 |
How it is calculated
Answer = number × percentage ÷ 100
Per cent means "out of 100", so 20% of a number is that number multiplied by 20 and divided by 100. To increase a number by a percentage, add the answer to it; to decrease it, subtract the answer.
Good to know
- To find 10% of a number, move the decimal point one place left. Halve that for 5%.
- A rise of 50% followed by a fall of 50% does not bring you back: you end up 25% lower.
- X% of Y is always the same as Y% of X, which can make mental maths easier.
Common questions
How do I find what percentage one number is of another?
Divide the first number by the second and multiply by 100. For example, 45 out of 60 is 45 ÷ 60 × 100 = 75%.
How do I work out a percentage increase?
Subtract the old value from the new value, divide by the old value and multiply by 100. From 400 to 500 is 100 ÷ 400 × 100 = 25%.
How do I convert a fraction to a percentage?
Divide the top number by the bottom number and multiply by 100. 3 out of 8 is 3 ÷ 8 × 100 = 37.5%.
How do I calculate percentage of marks?
Divide the marks you scored by the total marks and multiply by 100. 432 out of 500 is 86.4%.
Formula and text last reviewed in October 2026. Results are estimates, not financial advice.