Simplify Fractions Calculator
Reduce a fraction to its lowest terms and see the greatest common divisor.
Quick answer: Type the top and bottom numbers to reduce a fraction. For example 18/24 = 3/4, because both numbers divide by 6, their greatest common divisor.
How to use it
- Type the top and bottom numbers.
- The calculator finds the greatest common divisor (GCD) and divides both numbers by it.
- If the GCD is 1, the fraction is already in lowest terms.
Simplifying by hand
Find a number that divides both the top and the bottom, divide, and repeat until no number above 1 divides both. Handy tests: a number divides by 2 if it ends in an even digit, by 3 if its digits add up to a multiple of 3, by 5 if it ends in 0 or 5, and by 9 if its digits add up to a multiple of 9.
Examples
| Fraction | GCD | Lowest terms |
|---|---|---|
| 6/8 | 2 | 3/4 |
| 18/24 | 6 | 3/4 |
| 15/45 | 15 | 1/3 |
| 14/21 | 7 | 2/3 |
| 100/250 | 50 | 2/5 |
What people use it for
- Homework
- Checking answers
- Cooking and scaling
- Ratios
Questions
How do I simplify a fraction?
Divide the top and bottom by their greatest common divisor.
What does lowest terms mean?
The top and bottom share no common factor other than 1.
Is 7/13 in lowest terms?
Yes, because 7 and 13 share no common factor.
Is it free?
Yes. No sign-up, no install and no limit.
Is anything saved or sent?
No. Everything runs in your browser. Only your own best score, where a page shows one, is kept on your device.
Last updated 2026-10-24. Free to use, no sign-up. Made by ficklestudio26.