Simplify Ratio Calculator
Enter any ratio and this calculator reduces it to its simplest form. For example, 10:15 simplifies to 2:3. The calculator finds the GCD and divides both parts by it.
Examples
| Original | GCD | Simplified |
|---|---|---|
| 6:9 | 3 | 2:3 |
| 10:15 | 5 | 2:3 |
| 12:8 | 4 | 3:2 |
| 20:25 | 5 | 4:5 |
| 15:35 | 5 | 3:7 |
Simplify ratio: frequently asked questions
What does it mean to simplify a ratio?
Simplifying a ratio means reducing both parts to their smallest whole numbers while maintaining the same proportion. For example, 6:9 simplifies to 2:3 by dividing by the GCD of 3.
How do I simplify a ratio?
Find the greatest common divisor (GCD) of both numbers, then divide each by the GCD. For 8:12, GCD = 4, so 8/4 : 12/4 = 2:3.
When should I simplify a ratio?
Always simplify ratios to make them easier to understand and work with. For example, 50:100 simplifies to 1:2, which is much clearer.
Can a ratio be expressed as a fraction?
Yes. The ratio A:B can be expressed as the fraction A/B. Simplifying a ratio is identical to simplifying a fraction.
What if the GCD is 1?
If GCD is 1, the ratio is already in simplest form. For example, 3:5 cannot be simplified further.
Official sources
- Standard mathematical formula for ratio simplification.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.