Ratio Calculator

Simplify ratios, find missing values, and compare proportions.

Enter Ratio (e.g., 4 to 8)

Proportion (e.g., 4 : 8 :: 10 : ?)

Ratio 1 vs Ratio 2

Simplified Form

1 : 2

Understanding Ratios

To simplify a ratio, you divide both numbers by their Greatest Common Divisor (GCD).

4 : 8 \div 4 = 1 : 2

This represents the same relationship but with smaller, easier numbers.

A proportion states that two ratios are equal. You can use cross-multiplication to find a missing value.

a / b = c / x \to x = (c \times b) / a

If 4:8 equals 10:x, then x must be 20.

Two ratios are equivalent if their cross-products are equal.

(a \times d) == (b \times c)

Example: 1:2 is equivalent to 2:4 because 1×4 = 2×2.