Ratio Calculator

Divide both parts by their greatest common divisor (GCD). For 24:36: GCD = 12, so 24/12 : 36/12 = 2:3. The calculator automatically finds the GCD and simplifies to the lowest terms. It handles two-part ratios (a:b), three-part ratios (a:b:c), and any number of parts.

A proportion is two equal ratios: a/b = c/d. Cross-multiply to find the missing value. If 3/4 = x/20, then 3 x 20 = 4 x x, so x = 60/4 = 15. Enter three known values and the calculator solves for the fourth. This is useful for scaling recipes, maps, models, and unit conversions.

A ratio a:b means a/(a+b) of the first part and b/(a+b) of the second. A 3:2 ratio means 3/5 (60%) first and 2/5 (40%) second. The calculator shows both fractions and percentages for each part of the ratio, making it easy to understand proportional distributions.

Multiply both parts by the same number. To scale 2:3 to have a total of 50: each unit = 50/(2+3) = 10, so the scaled values are 20:30. The calculator lets you specify a target total or a target value for one part and scales the entire ratio proportionally.

Ratios appear everywhere: cooking recipes (2:1 flour to sugar), screen aspect ratios (16:9), financial ratios (debt-to-equity), map scales (1:50,000), mixing solutions (3:1 water to concentrate), gear ratios in engineering, and odds in probability. Understanding ratios is fundamental to proportional reasoning.