How to convert a percent to a decimal
Remove the percent sign and divide by 100:
Decimal = percent ÷ 100 Dividing by 100 is the same as moving the decimal point two places to the left, which is the quickest way to do it in your head:
- 25% → move the point two places left → 0.25
- 5% → 05. → 0.05 (add a zero to make room)
- 12.5% → 0.125
- 150% → 1.5
"Percent" means "per hundred", so 25% is 25 hundredths. Writing 25 hundredths as a decimal gives 0.25 — the number of wholes it represents.
What is −10% as a decimal?
−10% as a decimal is −0.1. The method is the same for negative percentages: divide by 100 and keep the sign. −10 ÷ 100 = −0.1.
Negative percentages usually describe a fall — a price change of −10% is a 10% decrease — and the decimal keeps the minus sign, which matters when you use it in a calculation. Multiplying by −0.1 gives the size of the drop; multiplying by 1 + (−0.1) = 0.9 gives the new value after it. For calculating the percentage change between two values, see the Percentage Change calculator.
Percentages under 1%
This is where the conversion most often goes wrong. 0.5% is 0.005, not 0.5 — 0.5 as a decimal would be 50%. The point moves exactly two places regardless of how small the number is, so 0.1% is 0.001 and 0.01% is 0.0001.
Percentages over 100%
100% is 1 as a decimal, so anything over 100% becomes a decimal greater than 1: 150% is 1.5, 200% is 2, and 1,250% is 12.5.
Percent to decimal chart
| Percent | Decimal |
|---|---|
| 1% | 0.01 |
| 5% | 0.05 |
| 10% | 0.1 |
| 12.5% | 0.125 |
| 20% | 0.2 |
| 25% | 0.25 |
| 33.3% | 0.333 |
| 50% | 0.5 |
| 75% | 0.75 |
| 90% | 0.9 |
| 100% | 1 |
| 125% | 1.25 |
| 150% | 1.5 |
| 200% | 2 |
| 0.5% | 0.005 |
| 0.1% | 0.001 |
| -5% | -0.05 |
| -10% | -0.1 |
| -25% | -0.25 |
| -50% | -0.5 |
Why convert percentages to decimals?
Decimal form is useful when a calculation or formula requires the percentage as a number. To find 15% of 80, multiply by the decimal: 0.15 × 80 = 12. To add 20% to a price, multiply by 1.2. Converting the percentage to decimal form also makes the size of the change explicit: 15% is 0.15, while 150% is 1.5.
Converting back: decimal to percent
Do the opposite: multiply by 100, or move the point two places to the right, and add a percent sign. 0.25 becomes 25%. The decimal to percent calculator does this for you.
Frequently asked questions
How do you convert a percent to a decimal?
Remove the percent sign and divide by 100 — or move the decimal point two places to the left. 25% becomes 0.25, and 5% becomes 0.05.
What is -10% as a decimal?
−0.1. Divide by 100 and keep the minus sign: −10 ÷ 100 = −0.1.
What is 0.5% as a decimal?
0.005. It's easy to write 0.5 by mistake, but 0.5 as a decimal is 50% — a hundred times larger.
What is 100% as a decimal?
1. One hundred percent is the whole of something, and the whole is 1. Percentages above 100% give decimals above 1.
Do I need to type the % sign?
No. The calculator reads 25 and 25% the same way.