Ratio Calculator

Interactive Studio

Simplify mathematical ratios to lowest terms, solve proportions (A:B = C:X), scale aspect ratios with live preview boxes, and divide quantities proportionally. Instant feedback with zero server storage.

Mode:

Simplify Ratio Inputs

A : B

Antecedent (A)

Consequent (B)

Simplified Result

16 : 9

Reduced from original ratio 1920 : 1080 (GCD: 120)

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About Ratio Calculator

A ratio describes the relative size of two or more values. This studio simplifies ratios to their irreducible forms using the Euclidean GCD algorithm, solves missing terms in proportions, scales aspect ratios for display resolutions, and divides lump sums into exact shares.

How to use Ratio Calculator

Enter the numbers of your ratio to simplify it, or enter the known terms of a proportion to solve the missing one.
Use the aspect-ratio mode with a width and height to get a screen ratio.
Use the share mode to divide a total into parts that follow a ratio.

Worked examples

Input: Simplify 24:36

Result: 2:3, because the greatest common divisor of 24 and 36 is 12.

Input: 1920 x 1080 aspect ratio

Result: 16:9.

Input: Split 500 in the ratio 2:3

Result: 200 and 300.

Background

A ratio is simplified by dividing every term by their greatest common divisor, found with the Euclidean algorithm. Two ratios are equal when their cross products match, so a/b = c/d means a x d = b x c. Solving a missing term uses that identity.

To share a total in a ratio, add the parts, divide the total by that sum, and multiply by each part.

Common mistakes

Reordering terms. 2:3 and 3:2 are different ratios.
Entering decimals when whole numbers are needed. Multiply every term by 10 or 100 first.
Dividing a total by the number of parts rather than the sum of the ratio terms.