Not sure where to put your projector? Enter the screen size and the throw ratio from the projector specs, and this calculator shows how far the lens should sit from the screen.
How it works
Throw distance is the throw ratio multiplied by the screen width. A projector with a 1.5 throw ratio needs 1.5 feet of distance for every foot of screen width. Zoom lenses give a range (for example 1.2 to 1.5), so the calculator shows a minimum and maximum distance.
Example: a 100 inch 16:9 screen is about 87 inches wide. With a 1.5 throw ratio, the projector sits about 131 inches (11 feet) from the screen.
Frequently asked questions
Where do I find the throw ratio?
It is listed in the projector specifications, often written as 1.2 to 1.5:1. If only one number is given, enter it in both boxes.
Does the distance include the projector body?
The distance is measured from the lens to the screen, so allow a little extra depth behind the lens for the projector body.
What if my projector has no zoom?
Use the same value for the minimum and maximum throw ratio. You then get one exact distance for that screen size.
