Projector Throw Calculator

The projector throw calculator works two ways: enter your throw distance and throw ratio to find the resulting screen size, width, and height -- or enter a desired screen diagonal and throw ratio to find out the required placement distance in feet and meters.

Calculated Screen Size

80"
diagonal
Width: 69.7"
Height: 39.2"

Throw Ratio Guide

0.3-0.5
Ultra Short Throw
Place inches from wall
0.5-1.0
Short Throw
Small rooms, close walls
1.0-2.0
Standard Throw
Most common projectors
2.0+
Long Throw
Large venues, auditoriums

Setup Visualization

Throw Distance

Throw Ratio = Distance / Screen Width. Lower ratios mean shorter distances for the same screen size.

Understanding Projector Throw Distance and Throw Ratio

Throw distance is the distance between your projector and the screen. The throw ratio describes the relationship between this distance and the resulting image width. Our projector throw calculator helps you determine the correct placement distance for your desired screen size, or find what screen size you'll get from a specific projector position. Once you know your screen size, use the projection screen calculator to get the exact width and height of the screen itself.

Understanding throw specifications is essential when planning a projector installation. Incorrect throw distance results in images that are too large, too small, or out of focus regardless of adjustment. If you are deciding between a projector and a flat-panel TV, our tv size calculator can help you compare the two approaches for your room. For a head-to-head view of different projected image sizes, the screen size tool lets you visualise multiple screen dimensions side by side.

Projector Types: Short Throw vs Long Throw

Ultra Short Throw (UST)

Ultra short throw projectors (ratio below 0.4) sit just inches from the screen, projecting upward. They're ideal for living rooms where ceiling mounting isn't possible and eliminate shadows from people walking in front of the projector.

Short Throw

Short throw projectors (ratio 0.4-1.0) need only 4-8 feet for a 100-inch image. They're popular for classrooms and small meeting rooms where space is limited and viewer shadows could be problematic.

Standard Throw

Standard throw projectors (ratio 1.0-2.0) require 10-15 feet for a 100-inch image. These are most common for home theaters where ceiling mounting at the back of the room is typical.

Long Throw

Long throw projectors (ratio above 2.0) are designed for large venues like auditoriums and lecture halls where the projector must be positioned far from the screen.

Projector Installation Considerations

Lens shift allows vertical and horizontal image adjustment without moving the projector, providing flexibility in mounting position. Projectors with generous lens shift are easier to install in non-ideal locations.

Consider zoom range when planning installations. A projector with 1.3x zoom can achieve the same image size from different distances, providing placement flexibility. Calculate both minimum and maximum throw distances for your target screen size.