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Ratio Calculator

Simplify ratios, find equivalent ratios, and solve proportion problems.

Results

Simplified Ratio3:2
A/B (decimal)1.5
Missing D (A:B = C:D)4
A as % of total60%
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What is Ratio?

The Ratio Calculator simplifies ratios to their lowest terms, finds equivalent ratios, and solves proportion problems (finding the missing value in A:B = C:D).

Ratios compare two quantities and are fundamental in math, cooking (recipe scaling), finance (debt-to-income ratio), science (concentration ratios), and everyday life (mixing ratios).

Simplifying a ratio means dividing both numbers by their GCD (Greatest Common Divisor). 12:8 simplifies to 3:2 because GCD(12,8) = 4.

Formula

Simplify: divide both by GCD(A,B) 12:8 → GCD = 4 → 3:2

Solve proportion A:B = C:D: D = (B × C) / A

A as percentage of total: A/(A+B) × 100

Examples: 12:8 = 3:2 15:25 = 3:5 If 3:2 = 6:?, then ? = (2×6)/3 = 4

How to use this Ratio Calculator?

1. Enter A and B to simplify the ratio A:B. 2. Enter C to solve the proportion A:B = C:D (find D). 3. See simplified ratio, decimal equivalent, missing value, and percentages.

Frequently asked questions

How to simplify a ratio?
Find the GCD (Greatest Common Divisor) of both numbers and divide. 24:36 → GCD=12 → 2:3. Or keep dividing by common factors until you can't anymore.
How to solve A:B = C:D?
Cross multiply: A×D = B×C, so D = (B×C)/A. Example: 3:4 = 9:? → ? = (4×9)/3 = 12.
What is the golden ratio?
The golden ratio (φ) ≈ 1.618. Two quantities are in the golden ratio if their ratio equals the ratio of their sum to the larger quantity. It appears in art, architecture, and nature.
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