> THROW DISTANCE CALCULATOR
Throw distance calculator
Work out the throw ratio your distance and screen size demand, and which projectors reach it.
Before you buy
What this calculator works out
Throw ratio is distance divided by image width, not the diagonal. Give us the screen size you want and how far back the projector will sit, and we return the ratio a projector has to be able to reach, plus every projector in this market whose published range contains it.
Why width and not the diagonal?
Because that is how manufacturers define the ratio. A 16:9 screen is about 0.872 times as wide as its diagonal, so using the diagonal overstates every distance by around 15 percent. Calculators that get this wrong send people home with a projector that cannot fill their wall.
Does zoom change the answer?
Yes, and that is why a projector has a range rather than a single figure. A 1.3 to 2.1 projector can sit anywhere in that band, so it passes if your required ratio falls inside it.