Fraction to Percent Calculator
Type the numerator and denominator of a fraction to see it as a percentage. The guide shows the formula, a mental shortcut for denominators such as 20 and 25, and a table of everyday fractions.
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Created by the Reeliy Editorial Team. Last updated: Oct 19, 2026
How to convert a fraction to a percentage
A percentage is a fraction whose denominator is 100, so "37%" means 37/100. To express any other fraction as a percentage, divide the numerator by the denominator and then multiply the result by 100.
percent = numerator ÷ denominator × 100
- Enter the numerator, the number above the bar, in the first box.
- Enter the denominator, the number below the bar, in the second box. It must not be zero.
- Press the button and read the percentage in the Percentage row.
Decimals and negative numbers are accepted in both boxes. The answer is rounded to four decimal places. A whole-number answer appears without decimals (3/4 gives 75%), one that needs only one or two decimals is written with two (1/8 gives 12.50%), and anything longer shows four (1/3 gives 33.3333%).
Worked examples
A test score: 17/20. Divide 17 by 20 to get 0.85, then multiply by 100: the score is 85%.
A fraction that does not divide evenly: 7/9. 7 ÷ 9 = 0.7777…, and 0.7777… × 100 = 77.7777…, which the calculator rounds to 77.7778%.
A part of a group: 45 out of 60. Write it as 45/60, which divides to 0.75. That is 75%. Reducing the fraction first gives the same answer, since 45/60 = 3/4.
An improper fraction: 5/4. When the numerator is larger than the denominator the percentage is above 100. Here 5 ÷ 4 = 1.25, so 5/4 is 125%: the part is one and a quarter times the whole.
A mixed number: 2 1/2. Convert it to an improper fraction first. 2 × 2 + 1 = 5, so 2 1/2 = 5/2, and 5 ÷ 2 × 100 = 250%.
A negative fraction: −3/8. The sign carries through the calculation. 3 ÷ 8 = 0.375, so −3/8 is −37.5%, displayed by the calculator as −37.50%.
A shortcut when the denominator divides 100
If the denominator is a factor of 100 (2, 4, 5, 10, 20, 25 or 50), you can skip the division. Multiply the numerator and the denominator by the same number to make the denominator 100, and the new numerator is the percentage.
- 3/20: multiply top and bottom by 5 to get 15/100, so 15%.
- 7/25: multiply by 4 to get 28/100, so 28%.
- 9/50: multiply by 2 to get 18/100, so 18%.
- 1/4: multiply by 25 to get 25/100, so 25%.
For other denominators, such as 3, 6, 7 or 9, the percentage does not come out as a whole number, and the division route above is the way to go.
Fraction to percent conversion table
| Fraction | Percent |
|---|---|
| 1/2 | 50% |
| 1/3 | 33.3333% |
| 2/3 | 66.6667% |
| 1/4 | 25% |
| 3/4 | 75% |
| 1/5 | 20% |
| 2/5 | 40% |
| 3/5 | 60% |
| 4/5 | 80% |
| 1/6 | 16.6667% |
| 5/6 | 83.3333% |
| 1/8 | 12.5% |
| 3/8 | 37.5% |
| 5/8 | 62.5% |
| 7/8 | 87.5% |
| 1/10 | 10% |
| 1/12 | 8.3333% |
| 1/16 | 6.25% |
| 1/20 | 5% |
| 1/25 | 4% |
| 1/50 | 2% |
| 3/2 | 150% |
Common mistakes
- Forgetting to multiply by 100. 3/4 is 0.75 as a decimal, but 75% as a percentage.
- Swapping the numbers. The part goes on top and the whole on the bottom. 15 out of 60 is 15/60 = 25%, not 60/15 = 400%.
- Assuming a percentage cannot pass 100. It can. A numerator larger than the denominator means the part is bigger than the reference amount.
- Treating a rounded value as exact. 33.3333% is slightly below one third, so three of those do not quite make 100%.
Related conversions
- Convert a percentage back into a fraction with the percent to fraction calculator.
- See the plain decimal value with the fraction to decimal calculator.
- Work out a percentage of any number, or a percent change, with the percentage calculator.
- Do arithmetic with fractions in the fraction calculator.
- The fraction to percent converter does the same job in converter form.
Frequently asked questions
How do you change a fraction to a percent?
Divide the numerator by the denominator, then multiply by 100. For example, 3/8 = 0.375 and 0.375 × 100 = 37.5%.
Can a fraction be more than 100 percent?
Yes. When the numerator is bigger than the denominator the fraction is greater than 1, so its percentage is greater than 100. For example, 5/4 is 125%.
How do I convert a mixed number such as 2 1/2 to a percent?
Turn it into an improper fraction (2 × 2 + 1 = 5, giving 5/2), divide (5 ÷ 2 = 2.5) and multiply by 100 to get 250%.
Why does the answer sometimes show two decimals and sometimes four?
The result is rounded to four decimal places. Values that need at most two decimals are written with two, such as 12.50%, and values that need more are written with four, such as 33.3333%. Whole numbers have no decimals.
What if the denominator is zero?
A fraction with a zero denominator is undefined, so the calculator asks for a non-zero denominator.
Cite this calculator and page
If you use this page in your work, you can cite it as:
Reeliy Editorial Team. (2026). Fraction to Percent Calculator. Reeliy. https://reeliy.com/calculators/fraction-to-percent-calculator“Fraction to Percent Calculator.” Reeliy, 2026, https://reeliy.com/calculators/fraction-to-percent-calculator.