Projector Throw Ratio & Screen Size Calculator

Calculate throw ratio, projection distance, image width and screen dimensions for any projector or projection lens.

Find Required Throw Ratio

Enter the required image width and lens-to-screen distance.

Image width and distance must use the same unit.

Calculate Projection Distance

Enter image width and the minimum and maximum throw ratio.

For a fixed throw ratio, enter the same value twice.

Calculate Image Width

Enter lens-to-screen distance and the projector or lens throw-ratio range.

Screen Size Converter

Convert diagonal screen size into image width and image height.

Enter diagonal size in inches.

How to Calculate Projector Throw Ratio

Throw Ratio = Lens-to-Screen Distance ÷ Image Width
Projection Distance = Image Width × Throw Ratio
Image Width = Lens-to-Screen Distance ÷ Throw Ratio

The calculator supports fixed throw ratios and variable throw-ratio ranges and can therefore be used with short throw, standard throw, long throw and other projector lens configurations.

Important: Calculated values are intended for initial optical planning. Final projector installation should also consider the actual projector, lens specification, zoom position, lens shift, mounting tolerance and site conditions.

Need Help Selecting a Projector?

Send SMX your image dimensions, projection distance, application and installation conditions. We can help evaluate a suitable projector brightness and throw ratio.

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