To convert a percentage to a fraction, write it over 100 and simplify. 37.5% is 37.5/100 = 375/1000, and dividing the top and bottom by 125 gives 3/8. Percentages over 100 become improper fractions: 150% is 3/2, or 1 1/2.
Formula
fraction = percentage ÷ 100, then simplify Examples
- 45% = 45/100 = 9/20.
- 12.5% = 125/1000 = 1/8.
Printable: Fraction to percent chart
Common mistakes
- Forgetting to simplify: 20/100 is right, but 1/5 is the expected answer.
- Treating 0.5% as 1/2. It is 1/200.
In Excel and Google Sheets
- Percentage in A2 (shows up to 3-digit denominators)
=TEXT(A2,"# ???/???")
FAQ
What is 33% as a fraction?
33/100. One third is 33⅓%, not 33%.
How do I simplify a fraction?
Divide the top and bottom by their greatest common divisor.
Can every percentage be written as a fraction?
Yes. Repeating ones like 33.333…% become simple fractions too: exactly 1/3.
How we calculate: exact decimal math (no rounding errors), you choose the decimal places, and your numbers never leave your browser. Methodology →
Updated October 2026