Ratio Calculator

Simplify ratios, solve proportions, and convert between ratio formats.

:

Simplified Ratio

3 : 2

As Fraction

3/2

As Decimal

1.5

As Percentage

150%

Ratio Calculator Formula & How It Works

Ratio a:b = a/b | Proportion: a/b = c/d → d = b×c/a
  • Simplify: divide both parts by GCD
  • Part-to-whole: ratio part ÷ total
  • Scaling: multiply both sides by same factor
  • Proportion: cross-multiply to find missing value

A ratio compares two quantities of the same type. The ratio 3:4 means for every 3 of the first quantity, there are 4 of the second. To simplify, divide both terms by their GCD. For proportion a:b = c:d, solve using cross-multiplication: a×d = b×c.

Ratio Calculator FAQs

How do you simplify a ratio?

Divide both terms by their Greatest Common Divisor (GCD). Ratio 12:8 → GCD(12,8)=4 → 12/4 : 8/4 = 3:2. Always check: are there common factors? Keep dividing until no common factors remain.

How do you find a missing value in a proportion?

Cross-multiply and divide. For a/b = c/x: x = (b×c)/a. Example: 3/4 = 9/x → x = (4×9)/3 = 12. Check: 3/4 = 9/12 = 0.75 ✓.

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