Ratio Simplifier — Reduce a:b to Lowest Terms
Enter two numbers and this ratio simplifier divides both by their greatest common divisor to show the ratio in its simplest form, such as 1920:1080 becoming 16:9.
Enter the two numbers of the ratio to see the simplified result.
How it works
What is a simplified ratio?
A ratio compares two quantities, written as a:b. Simplifying a ratio means rewriting it with the smallest whole numbers that keep the same proportion.
For example, 1920:1080 simplifies to 16:9 because both numbers share a common factor of 120.
How simplification works
The tool finds the greatest common divisor (GCD) of the two numbers and divides both by it. The result is the ratio in its lowest terms, where the only shared factor is 1.
Frequently asked questions
›What does it mean to simplify a ratio?
It means dividing both numbers by their greatest common divisor so the ratio uses the smallest possible whole numbers while keeping the same proportion.
›Can I simplify a ratio with decimals?
This tool works with whole numbers. Multiply both values by a power of ten to remove decimals before entering them.
›What is the greatest common divisor?
The GCD is the largest number that divides both values evenly. Dividing by it gives the ratio in lowest terms.
›Why does 1920:1080 become 16:9?
Both numbers share a common factor of 120. Dividing each by 120 leaves 16:9, the standard widescreen aspect ratio.
›Is a ratio of x:1 fully simplified?
Yes. When the second number is 1 and the first is a whole number, the ratio is already in its lowest terms.
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