Projector Throw Calculator
Solve projector throw distance, image width, or throw ratio from the other two, with screen-diagonal helpers.
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Distance ÷ image width. Check the projector spec sheet.
Results
- Throw distance
- 130.5 in (10.88 ft)
- Throw ratio
- 1.5:1
- Image width
- 87 in
- Throw distance
- 130.5 in
distance = throw ratio × image width. Zoom lenses cover a ratio range (e.g. 1.5–2.2:1); ultra-short-throw projectors are below 0.4:1 and sit right under the screen. Measure from the lens, not the projector body.
About Projector Throw Calculator
The whole relationship is distance = throw ratio × image width; give any two and the third is solved. A helper converts a screen diagonal and aspect ratio into image width, and presets cover standard (1.5–2.2:1), short (0.4–1:1), and ultra-short-throw (<0.4:1) lenses.
Common uses
- Check whether a projector fits your room before buying
- Find the mounting distance for a chosen screen size
- Work out what screen size an existing mount position produces
Example
Input
Throw ratio 1.5:1 · 100" wide image
Output
150" (12.5 ft) throw distance
Limitations
- Zoom lenses span a ratio range — compute both ends. Measure from the lens; offset and lens shift are not modeled.