🧮 Advanced Ratio Calculator

Work with ratios of two or three numbers. Simplify ratios, find equivalent ratios, scale them up or down, convert to 1:n or n:1 form, and see a small visual of how each part compares to the whole.

⚠ Please enter valid positive numbers for the highlighted fields.

Ratio Setup

Ratio of�

I would like to�

A:B = C:D • Enter any three values to calculate the fourth (leave one box blank).

A : B = C : D

Enter any 3 values to calculate the 4th when using �find an equivalent ratio�.

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How ratio calculations work (example)

Suppose you want an equivalent ratio to 2:3 where the first number becomes 8.

  1. Start with 2 : 3.
  2. To turn 2 into 8, multiply by 4 ? scale factor k = 4.
  3. Multiply both parts by 4: 2×4 : 3×4 = 8 : 12.
  4. Simplify 8 : 12 by dividing both by GCD(8,12)=4 ? 2 : 3 (same ratio).

Our calculator applies the same idea for equivalent ratios, simplifying, and converting to 1:n or n:1 forms.

Multiple tools

Equivalent ratios, scaling, simplifying and 1:n / n:1 conversions.

Visual check

See how each part compares to the whole using a simple chart.

Math & real life

Helpful for recipes, mixing, map scales, and classroom problems.

Privacy friendly

All calculations run in your browser. Nothing is stored or sent.