ToolBark
Math

Ratio Simplifier

Simplify any ratio to lowest terms — instantly.

Enter Ratio

Simplified Ratio

Lowest Terms2 : 3reduced by a factor of 2
Original ratio4 : 6
Simplified ratio2 : 3
Common factor (GCD)2
Decimal value (A ÷ B)0.66666667
A as % of B66.6667%

Scale Ratio

Set one term to a specific value and the other term(s) will be scaled proportionally.

Scaled Result
1 : 1.5

Multiplier: ×0.5

2 : 31 : 1.5

How it works

Simplifying a ratio
Divide all terms by their Greatest Common Divisor (GCD) to get the smallest whole-number ratio.
GCD (Greatest Common Divisor)
The largest integer that divides every term evenly. Found using Euclid's algorithm.
Scaling a ratio
Multiply all terms by the same factor so one term equals your target value while preserving proportions.
Three-term ratios (A : B : C)
Works the same way — GCD divides all three terms simultaneously to reach lowest terms.
About

A ratio simplifier reduces any ratio — like 12:8 or 15:10:25 — to its lowest terms by dividing all parts by their Greatest Common Divisor. Use this free tool to simplify two-term or three-term ratios instantly, including those with decimals. You can also scale a simplified ratio so that one term equals any target value, making it easy to apply proportions in recipes, maps, or design work.

FAQ
How do you simplify a ratio to lowest terms?+

Find the Greatest Common Divisor (GCD) of all terms, then divide each term by the GCD. For example, 12:8 has a GCD of 4, so it simplifies to 3:2.

Can I simplify a ratio that has decimals?+

Yes. The tool first scales all decimal values to integers (e.g. 1.5:2.5 becomes 15:25), then divides by the GCD to get 3:5.

What does scaling a ratio mean?+

Scaling sets one term to a specific value and adjusts the other terms by the same multiplier, preserving the proportion. For example, scaling 2:3 so the first term is 10 gives 10:15.

Does the tool support three-term ratios like A:B:C?+

Yes. Enable the third-term input and enter all three values. The GCD is computed across all three terms simultaneously to reduce the ratio to its simplest form.

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