Home › Calculators › Ratio Calculator
Enter a ratio like 3:4, tell the tool which side you know the real value of, and it finds the other side — plus the simplified ratio. Perfect for recipes, scale models, mixing paint and map scales.
6:8 and 3:4 are the same ratio — dividing both sides by their greatest common divisor gives the simplest form.
If a recipe's 3:4 ratio needs 12 cups of flour on the "3" side, the "4" side is 12 × 4/3 = 16 cups. That cross-multiplication is all the tool does — instantly and without arithmetic slips.
Divide both parts by their greatest common divisor: 6:8 → 3:4.
An equation of two ratios, like 3/4 = 12/16 — the basis for scaling recipes, maps and models.
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