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Projector throw distance calculator
Throw distance = throw ratio × image width. For a 100-inch 16:10 screen (2.15 m wide) a standard 1.5:1 lens sits about 3.2 m back, a short throw at 0.6:1 about 1.3 m, and an ultra short throw at 0.3:1 about 0.6 m.
Enter your screen size to see how far each lens class sits from the screen and which of our 152 in-stock projectors can produce that image, or start from the space you have and see which fit. Distances are calculated from each manufacturer's stated throw ratio and image size limits.
Throw distance = throw ratio × image width. Every projector below lists its own exact range.
In-stock projectors for a 100-inch image 148 can produce it, closest to the screen first
Showing 8 of 148. Switch to "Which projectors fit my room?" to narrow them by the space you have, or browse all projectors.
Throw distance by screen size
Lens-to-screen distance for the common screen sizes at 16:10, the native format of most business projectors. A 16:9 screen of the same diagonal is about 3% wider, so add 3% to each figure.
| Screen size | Image width | Ultra short throw (0.3:1) | Short throw (0.6:1) | Standard throw (1.35 to 2.2:1) |
|---|---|---|---|---|
| 60" | 1.29 m | 0.4 m | 0.8 m | 1.7 m to 2.8 m |
| 80" | 1.72 m | 0.5 m | 1.0 m | 2.3 m to 3.8 m |
| 100" | 2.15 m | 0.6 m | 1.3 m | 2.9 m to 4.7 m |
| 120" | 2.58 m | 0.8 m | 1.6 m | 3.5 m to 5.7 m |
| 150" | 3.23 m | 1.0 m | 1.9 m | 4.4 m to 7.1 m |
Want the mounting position and a preview on your wall?
The projector screen size calculator takes the picture size you want and the depth you have, shortlists the projectors that fit, suggests where to mount each one and previews the image at real scale on a photo of the wall.
Throw distance questions, answered
How is projector throw distance calculated?
Throw distance = throw ratio × image width. A projector with a 1.5:1 throw ratio needs 1.5 metres of distance for every 1 metre of image width. The ratio uses the image's width, not its diagonal; a 100-inch 16:10 screen is about 2.15 m wide, so that projector would sit around 3.2 m back. Projectors with zoom lenses quote a range, such as 1.35 to 2.2:1, giving flexibility in where to mount.
How far should a projector be from a 100 inch screen?
For a 100-inch 16:9 screen, which is 2.21 m wide, a standard lens with a 1.35 to 2.2:1 throw ratio sits 3.0 m to 4.9 m from the screen, a short throw at 0.6:1 sits about 1.3 m back, and an ultra short throw at 0.3:1 about 0.7 m back. A 100-inch 16:10 screen is slightly narrower at 2.15 m, so each distance is about 3% shorter. Check the throw ratio on the projector's spec sheet and multiply it by your screen's width for the exact figure.
What throw ratio do I need?
Divide the distance you have from lens to screen by the width of the image you want. A room that allows 3 m for a 120-inch 16:10 image (2.58 m wide) needs a throw ratio of about 1.16:1, which is the wide end of a standard zoom lens or a short throw model. Below about 1:1 you need a short throw projector, and below about 0.4:1 an ultra short throw.
What is a short throw projector?
Short throw projectors have a throw ratio below roughly 1:1, producing a large image from very close to the screen, ideal for classrooms and small meeting rooms where presenters would otherwise cast shadows. Ultra short throw models go further still, sitting just centimetres from the wall.
Does the aspect ratio change the throw distance?
Yes, because throw distance depends on the image's width and the same diagonal is a different width at each aspect ratio. A 100-inch image is 2.21 m wide at 16:9, 2.15 m at 16:10 and 2.03 m at 4:3, so at a 1.5:1 throw ratio the projector sits at 3.3 m, 3.2 m or 3.0 m respectively. Use the aspect ratio of the content you will show most, which for business projectors is usually the 16:10 native format.
Replacing a projector on an existing mount? The projector replacement calculator works backwards from the distance and picture you already have. Read the full answer to how far a projector should be from the screen, or browse ultra short throw projectors and all projectors. Fitting a flat-panel display instead? Use the screen size calculator to match a display to your room.
Need help specifying a projector for your space? Our technical team can advise on installation, mounting and compatible AV systems: talk to us.
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