How do I calculate Projector Screen Dimensions?

Calculating Projector Screen Dimensions for 16:9 Projectors

Here are your basic formulas for calculating projector screen dimensions. They are slightly rounded for your convenience.

All calculations are based on the screen area, and do not include the borders or frame. These calculations are for standard 16:9 aspect ratio screens (HDTV shape), which are used by the vast majority of home theater users, as the vast majority of home theater projectors are 16:9 native aspect ratio. Simply put, a 16:9 projection screen is 1.78 times as wide as it is high. 16 / 9 = 1.78 (rounded) If you know your projector screen's diagonal size:

Projector Screen Height: To calculate the projector screen height, multiply the diagonal by approximately 0.495. (In other words the height of the screen is just a bit less than 50% of the diagonal.

Projector Screen Width: The width of the projector screen is approximately 87% of the projector screen's diagonal, so multiply the diagonal measurement by approximately 0.87.

Examples:
Diagonal Size of a home theater projector screen: 100"
Projector screen height: 0.495 x 100" = 49.5 inches
Projector screen width: 0.87 x 100" = 87 inches
Diagonal Size of a home theater projection screen: 110"
Projector screen height: 0.495 x 110" = 54.5"
Projector screen width: 0.87 x 110" = 95.7"
If you know projection screen width, and need to calculate diagonal size and height of the screen:
Projector screen diagonal: To calculate the projector screen diagonal from the known width, divide the width by 0.87

Projector screen height: To calculate the projection screen height, from the known width, multiply the width by 0.57

Examples:
Width of a home theater projector screen: 100"
Projector screen diagonal: 100" / 0.87 = 115"
Projector screen height: 100" * 0.57 = 57"
Width of a home theater projection screen: 80"
Projector screen diagonal: 80 " / 0.87 = 92 "
Projector screen height: 80 " * 0.57 = 45.6 "