Projector Throw Distance
Calculator.
Calculate projector placement, image width, height and diagonal using the lens throw-ratio range. Type a distance, move the slider or drag the projector—the visual simulation and every measurement update together.
Plan the placement.
3.43 × 1.93 m
This calculator estimates placement using the entered throw-ratio range. Exact lens shift, image offset, focus limits, mounting clearance and model-specific restrictions must be confirmed using the projector manufacturer’s documentation.
How projector distance is calculated.
Projector throw ratio describes the relationship between lens-to-screen distance and projected image width. A 1.50:1 throw ratio means that every one metre of image width requires approximately 1.50 metres of throw distance.
A zoom lens has minimum and maximum throw ratios. At one fixed projector position, changing the lens zoom changes the possible image width. Use the exact lens specification rather than the projector model alone when working with interchangeable-lens projectors.
Image width = throw distance ÷ throw ratio
Image height = image width × aspect-height ÷ aspect-width
Floor, ceiling and rear projection.
The selected placement changes the visual planning view, while the basic horizontal throw-distance formula remains the same. Ceiling installations additionally require the correct mount, vertical lens shift, image offset and safe structural fixing.
For rear projection, measure throw distance from the projector lens to the rear surface of the screen. Allow additional clearance for the projector body, ventilation, cabling, access and audience-safe barriers.
Projection calculator questions.
Where can I find a projector’s throw ratio?
Check the projector or lens datasheet, installation manual or manufacturer’s official calculator. Large-venue projectors may support multiple lenses, each with a different throw-ratio range.
Is throw distance measured from the projector body?
Normally it is measured from the projector lens to the projection surface. The projector body depth and installation clearance must be added separately when planning the available room space.
Why does the image-size result show a range?
A zoom lens has minimum and maximum throw ratios. At one fixed distance, these ratios create the smallest and largest possible image widths.
Does ceiling mounting change the throw distance?
The horizontal throw calculation generally remains based on image width and lens ratio. Ceiling mounting affects vertical position, lens shift, offset, orientation, access and mounting safety.
Can I use this result for final installation?
Use it for planning and equipment selection. Final placement must be checked against the exact projector, compatible lens, manufacturer limits and site conditions.