OneTool

Ratio Calculator

Simplify, scale, and solve ratio problems with clear labeled steps.

Simplify a ratio

Simplified: 2 : 3

Scale a ratio to a target

Apply target to

Scaled ratio (from A:B above): 20 : 30

Solve proportion X:Y = Z:W

Leave exactly one box empty.

Missing value: 15

What is this tool?

Ratios compare quantities; proportions equate two ratios. Use this tool to reduce a ratio to lowest terms, scale it so one side matches a target, or leave one term blank in a proportion to solve for the missing value.

How to use it

  1. Simplify: enter A and B to get the reduced ratio.
  2. Scale: set a target for side A or B using the same A:B above.
  3. Proportion: fill three of X,Y,Z,W and leave one blank to solve.