Ratio Calculator
Simplify a ratio (16:9 to its lowest terms) or solve a proportion (a:b = c:d) for the missing value.
Ratio
:
Simplified ratio
16:9
Decimal: 1.7778
Frequently Asked Questions about the Ratio Calculator
What is a ratio?
A ratio compares two quantities by division. The ratio 3:4 means for every 3 units of the first, there are 4 of the second. Ratios are written with a colon, as a fraction, or as a decimal.
How do I simplify a ratio?
Divide both sides by their greatest common divisor. The ratio 12:18 has GCD 6, so it simplifies to 2:3. The calculator also scales decimal inputs by a power of 10 first, so 0.4:0.6 becomes 2:3.
How do I solve a proportion like 3:4 = x:20?
Cross multiply: 3 x 20 = 4 x, so x = 60 / 4 = 15. The calculator does this automatically when you leave one of the four positions blank.
What is the aspect ratio of a screen?
The ratio of width to height. A 1920 x 1080 display has the ratio 1920:1080, which simplifies to 16:9. Common ratios are 16:9 (widescreen), 4:3 (older TVs), and 21:9 (ultrawide).
Where are ratios used in everyday life?
Recipes (2 cups flour to 1 cup sugar), map scales (1 inch to 10 miles), gear ratios in vehicles, mixing paint or fuel, financial ratios in accounting, and screen and photo aspect ratios.