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Ratio Calculator

Simplify ratios to lowest terms and solve proportions with a single unknown.

Simplified ratio
2 : 3
Decimal form: 0.6667

Two Tools in One

Simplify any ratio to its lowest terms using the GCD, or solve a proportion with one unknown (X:Y = A:?). Handles decimals, integers, and multi-term ratios like 3:5:7.

Real-World Uses

  • Recipe scaling (butter:flour:sugar)
  • Mixing paints, cement, fertilizer
  • Aspect ratios (photo, video, screen)
  • Financial ratios and team allocations

Frequently Asked Questions

How do I simplify a ratio?

Find the greatest common divisor (GCD) of both numbers and divide each side. 24:36 → GCD 12 → 2:3. We do it automatically for any number of terms.

How do I solve a proportion?

Cross-multiply. If 3:4 = 9:?, then ? = (4 × 9) / 3 = 12. Enter three values and the tool solves for the fourth.

What about ratios with decimals?

Multiply each side by 10 or 100 until they're whole, then simplify. 1.5:2.5 → 15:25 → 3:5. Our tool handles decimals directly.

Can I simplify 3-term ratios?

Yes. 12:18:24 simplifies to 2:3:4 using the GCD of all three values. The calculator supports any number of terms.

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