Throw Distance Chart
Throw distance is how far the projector sits from the screen. This chart gives the distance for four common throw ratios and four 16:9 screen sizes. Print it and tape it to your setup notes.
The formula
Distance = throw ratio × image width
Image width comes from the diagonal: for a 16:9 screen, width = diagonal × 0.8716 (16 ÷ √(16² + 9²)). Height is not needed for the distance.
Worked example: a 100 inch 16:9 screen is 87.16 inches wide. With a throw ratio of 1.2, the distance is 1.2 × 87.16 = 104.6 inches, which is 8.71 ft or 2.66 m.
Image width for each diagonal (16:9)
| Diagonal | Width (in) | Width (ft) | Width (m) |
|---|---|---|---|
| 60 in | 52.29 | 4.36 | 1.33 |
| 80 in | 69.72 | 5.81 | 1.77 |
| 100 in | 87.16 | 7.26 | 2.21 |
| 120 in | 104.59 | 8.72 | 2.66 |
Throw distance chart
Distances are measured from the screen to the projector lens. Read across for the throw ratio on your projector's specification sheet, and down for your screen size.
| Throw ratio | 60 in screen | 80 in screen | 100 in screen | 120 in screen |
|---|---|---|---|---|
| 0.8 | 3.49 ft / 1.06 m | 4.65 ft / 1.42 m | 5.81 ft / 1.77 m | 6.97 ft / 2.13 m |
| 1.0 | 4.36 ft / 1.33 m | 5.81 ft / 1.77 m | 7.26 ft / 2.21 m | 8.72 ft / 2.66 m |
| 1.2 | 5.23 ft / 1.59 m | 6.97 ft / 2.13 m | 8.71 ft / 2.66 m | 10.46 ft / 3.19 m |
| 1.5 | 6.54 ft / 1.99 m | 8.72 ft / 2.66 m | 10.89 ft / 3.32 m | 13.07 ft / 3.98 m |
How to use the chart
- Find the throw ratio in your projector's specifications. Manufacturers list it as a ratio, sometimes with a range; use the value that matches your model.
- Choose the screen diagonal you plan to use.
- Read the distance where the row and column meet. Use it as a starting point, then adjust with the projector's zoom and lens shift if it has them.
- Measure from the screen surface to the front of the lens, not to the base of the projector.
Limits of this chart
- It covers 16:9 screens only. For 4:3 or 2.35:1 images, the width in step one is different.
- It gives the nominal distance for the stated ratio. Real zoom range, lens shift and offset change the usable placement.
- Ratios shown are the ones most often listed; check your own model's sheet, because some projectors sit outside this range.
- Figures are rounded to two decimals and are a calculation, not a measurement of any product.
For brightness, see the brightness calculator. For image sizing, see the projector calculator.