Tiny Toolkit

Ratio Calculator

Reduce any ratio to its simplest form using the GCD algorithm, or solve a proportion to find a missing value in A:B = C:X. Both modes update in real time. Useful for scaling recipes, reading map scales, comparing rates, and any situation where you need to reason about relative quantities.

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Frequently Asked Questions

How do you simplify a ratio?
Divide both values by their Greatest Common Divisor (GCD). For example, 12:8 → GCD is 4 → simplified to 3:2.
What is a proportion?
A proportion states that two ratios are equal: A:B = C:X. If you know three of the four values, you can solve for the missing one using cross-multiplication: X = (B × C) / A.
What is a ratio used for?
Ratios are used in cooking (recipe scaling), maps (scale ratios), finance (P/E ratios), photography (aspect ratios), and many other real-world contexts.

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