Know your room size but not which projector fits it? Enter the distance from the lens to the screen and the screen size, and this calculator gives the throw ratio you should look for.
How it works
Throw ratio equals the distance from the lens to the screen divided by the screen width. Below 0.4 is ultra short throw, 0.4 to 1.0 is short throw, 1.0 to 2.0 is standard throw, and above 2.0 is long throw.
Example: a projector 12 feet (144 inches) from a 100 inch 16:9 screen (87 inches wide) needs a throw ratio of about 1.65.
Frequently asked questions
What is a good throw ratio for a small room?
Short throw or ultra short throw projectors work best in small rooms because they fill a large screen from close range.
Should I match the ratio exactly?
Not exactly. Many projectors have a zoom lens, so pick one whose throw ratio range includes the number you get here.
Does the aspect ratio change the result?
Yes. A 16:10 or 4:3 screen of the same diagonal is a different width, which changes the ratio slightly.
