Projector Throw Distance Calculator

Calculate the screen size you'll get from your projector distance, or find the required distance for your desired screen size

Screen Size *

Projector Type

Aspect Ratio

About This Calculator

Projector placement is critical for getting the right image size. Too close and you won't fill your screen; too far and you'll overflow it. This calculator helps you find the perfect distance for your desired screen size, or determine what screen size you'll get from your available space.

How to Use

1 Choose whether you know your screen size or throw distance
2 Select your projector type (UST, short throw, standard, or long throw)
3 Enter your known value (screen size or distance)
4 Select your screen's aspect ratio
5 Click Calculate to see the results and distance range

FAQ

What is throw ratio?

Throw ratio is the distance from projector to screen divided by the screen width. A projector with 1.5:1 throw ratio needs to be 1.5 feet away for every foot of screen width. Lower ratio = shorter distance needed.

What's the difference between UST, short throw, and standard projectors?

Ultra Short Throw (UST): Sits inches from wall, 0.2-0.4 ratio
Short Throw: 3-8 feet for 100", 0.4-0.8 ratio
Standard: 10-15 feet for 100", 1.2-2.0 ratio
Long Throw: 15+ feet for 100", 2.0+ ratio

Where do I find my projector's throw ratio?

Check your projector's specification sheet—it's usually listed as "throw ratio" (e.g., 1.2:1 - 1.5:1). If given as a range, your projector has optical zoom. You can also find it on sites like ProjectorCentral.com by searching your model.

How far should I sit from the projector screen?

For 1080p content, sit at least 1.5x the screen diagonal away. For 4K content, you can sit closer (1-1.2x diagonal) without seeing pixels. For a 100" screen: 1080p: ~12-15 feet, 4K: ~8-10 feet.

Can I use a projector in a small room?

Yes, with the right projector. Ultra short throw projectors can create 100"+ images while sitting inches from the wall. Short throw projectors work well in rooms where you can't ceiling-mount far from the screen. Standard projectors need more distance.

Do I need a special screen for a projector?

A dedicated screen significantly improves image quality over a painted wall. For dark rooms, a white matte screen works well. For rooms with ambient light, consider a gray screen or ALR (Ambient Light Rejecting) screen. UST projectors often benefit from specialized UST screens.

Calculator Limitations

• Uses typical throw ratios for each category—your specific projector may differ.
• Doesn't account for lens shift, which can offset the projected image.
• Keystone correction (if needed) may slightly reduce effective image size.
• Always verify with your projector's specific throw ratio from the manual.

Projector Throw Distance Calculator

Further Reading

Your TV Is the Wrong Size for Your Room