In this guide
Quick answer: to find a percentage of a number, multiply the number by the percentage and divide by 100. For 10%, just move the decimal point one place to the left.
Percentage of common numbers
| Number | 5% | 10% | 15% | 20% | 25% |
|---|---|---|---|---|---|
| 10 | 0.5 | 1 | 1.5 | 2 | 2.5 |
| 20 | 1 | 2 | 3 | 4 | 5 |
| 25 | 1.25 | 2.5 | 3.75 | 5 | 6.25 |
| 40 | 2 | 4 | 6 | 8 | 10 |
| 50 | 2.5 | 5 | 7.5 | 10 | 12.5 |
| 60 | 3 | 6 | 9 | 12 | 15 |
| 75 | 3.75 | 7.5 | 11.25 | 15 | 18.75 |
| 80 | 4 | 8 | 12 | 16 | 20 |
| 100 | 5 | 10 | 15 | 20 | 25 |
| 120 | 6 | 12 | 18 | 24 | 30 |
| 150 | 7.5 | 15 | 22.5 | 30 | 37.5 |
| 200 | 10 | 20 | 30 | 40 | 50 |
| 250 | 12.5 | 25 | 37.5 | 50 | 62.5 |
| 500 | 25 | 50 | 75 | 100 | 125 |
| 1,000 | 50 | 100 | 150 | 200 | 250 |
Shortcuts for mental math
- 10%: move the decimal one place left. 10% of 250 is 25.
- 5%: half of 10%. 5% of 250 is 12.5.
- 20%: double 10%. 20% of 250 is 50.
- 15%: 10% plus 5%. 15% of 250 is 25 + 12.5 = 37.5.
- 25%: a quarter, or half of 50%. 25% of 250 is 62.5.
Numbers that are not in the table
Split the number into parts that are in the table. For 15% of 340, work out 15% of 300 (45) and 15% of 40 (6), then add them: 51.
Going the other way
To find what percent one number is of another, divide and multiply by 100. 12 out of 80 is 15%. The percentage calculator does all three common percentage questions, and our guide on percentage increase and decrease covers changes.
Where this comes in handy
The most common uses are tips (see the tip calculator), sale prices (the discount calculator), sales tax and pay raises.
Try the calculators
- Percentage Calculator: Percent of, what percent, percent change
- Discount Calculator: Sale price and how much you save
- Tip Calculator: Tip and split the bill
General information only, not professional advice. See our editorial policy.