Turning a decimal into a percent is one of the quickest conversions in maths, and one of the easiest to get wrong by a factor of ten.
Both directions work, and the nearest simple fraction is shown alongside.
How to use the Decimal to Percent Converter#
- Choose a direction. Decimal to percent, or percent to decimal.
- Enter the number. Type the decimal, or the percentage without the % sign.
- Read the result. The result also gives the nearest simple fraction.
The rule#
0.375 becomes 37.5 percent, which is 3/8 as a fraction. In practice you move the decimal point two places to the right. To go back, move it two places to the left: 12 percent becomes 0.12.
Common conversions#
| Decimal | Percent | Fraction |
|---|---|---|
| 0.1 | 10% | 1/10 |
| 0.25 | 25% | 1/4 |
| 0.333… | 33.3% | 1/3 |
| 0.5 | 50% | 1/2 |
| 0.75 | 75% | 3/4 |
| 1.5 | 150% | 3/2 |
Why decimals can be above 1#
A decimal of 1 is 100 percent, the whole. A decimal above 1 is more than the whole, which is why 1.5 is 150 percent. A negative decimal gives a negative percent. See the percentage calculator for percentages of a number.
Examples above and below one#
Small and large decimals follow the same rule. Move the decimal point two places to the right.
| Decimal | Percent |
|---|---|
| 0.005 | 0.5% |
| 0.05 | 5% |
| 0.8 | 80% |
| 1 | 100% |
| 2.5 | 250% |
To find a share of a quantity, multiply by the decimal. 0.375 of 80 is 30, which is the same as 37.5 percent of 80. If the decimal repeats, such as 0.3333, round the percent to the precision you need, here 33.3 percent.
Decimals, fractions and percents side by side#
A percent is a number out of 100, so you can move between a decimal and a percent by shifting the decimal point two places. A decimal of 0.35 is 35 percent, and 35 percent is 0.35. Fractions fit the same pattern, since a percent is a fraction with 100 on the bottom.
| Decimal | Percent | Fraction |
|---|---|---|
| 0.5 | 50% | 1/2 |
| 0.25 | 25% | 1/4 |
| 0.125 | 12.5% | 1/8 |
| 0.2 | 20% | 1/5 |
| 0.333… | 33.33% | 1/3 |
| 0.75 | 75% | 3/4 |
| 0.05 | 5% | 1/20 |
| 0.007 | 0.7% | 7/1000 |
The calculator also finds the nearest simple fraction. When the decimal repeats, such as 0.3333, it shows “About 1/3", because the match is close but not exact.
Common mistakes#
The biggest error is mixing up 0.5 and 0.5 percent. 0.5 as a decimal is 50 percent, but 0.5 percent as a decimal is 0.005. When someone says “the interest rate is 0.5", ask whether they mean 0.5 percent or 50 percent. A second mistake is shifting the point the wrong way. To convert a decimal to a percent you multiply by 100, which moves the point to the right, and to convert back you divide by 100, which moves it to the left.
In spreadsheets, formatting a cell as a percent multiplies the displayed value by 100 and adds the symbol, but the stored value stays the same. If you type 5 into a cell that is already formatted as a percent, you get 5 percent, but if you type 5 into a general cell and then switch the format, you get 500 percent.
Values above 1 and below 0.01#
A decimal of 1.5 is 150 percent, which means one and a half times the base amount. A decimal of 2 is 200 percent, a doubling. These come up with growth, where sales at 1.2 times last year’s are 120 percent of it, an increase of 20 percent. A decimal like 0.004 is 0.4 percent, as in a success rate of four per thousand. If you are working with an increase, use the percentage increase calculator, and for a fall use the percentage decrease calculator.
Everyday uses#
- Turning an exam score of 0.82 into 82 percent for a report.
- Reading a probability of 0.035 as 3.5 percent.
- Converting a tax or interest rate from a formula, such as 0.075 for 7.5 percent VAT, into a percent for a label.
- Checking a spreadsheet, where a value shown as 0.2 may need formatting as 20 percent.
Frequently asked questions#
Multiply by 100, or move the decimal point two places to the right.
Divide by 100, or move the decimal point two places to the left.
No. 0.5 is 50 percent. 5 percent is 0.05.
Yes. It means more than the whole amount.
0.5 is 50 percent, because 0.5 × 100 = 50. It is also the fraction 1/2. Be careful not to confuse it with 0.5 percent, which is a very different amount: 0.5% = 0.005 as a decimal, or 5 in every 1,000.