Ratio Calculator (Simplifier)

Simplify a ratio and see it as a decimal and a 1-based scale. Enter the two terms.

Simplified Ratio
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Lowest terms.

Usage Tip

Common screen ratios: 16:9 (widescreen), 4:3 (older), 21:9 (ultrawide). Simplifying shows whether two ratios match.

THE MATH
Simplified ratio = each term ÷ their greatest common factor
Decimal = A ÷ B
A ratio compares two quantities. Dividing both terms by their greatest common factor gives the simplest whole-number form.
16:9 and 1920:1080 are the same ratio.
Whole-number inputs give an exact simplified ratio; decimals are scaled to a 1-based form.
The decimal A/B and a 1:x scaling are also shown.
The second term cannot be zero.
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