Projector Throw Distance Calculator Epson

Calculator Form

Room name

Screen input basis

Measurement unit

Screen diagonal

Screen width

Aspect ratio

Custom aspect width

Custom aspect height

Editable lens preset

Minimum throw ratio

Maximum throw ratio

Known throw distance

Screen bottom height

Ceiling height

Vertical offset percent

Horizontal lens shift percent

Projector lumens

Screen gain

Cable extra percent

Installation notes

Example Data Table

Use case	Screen	Aspect	Throw ratio	Approximate distance
Home cinema wall	100 in diagonal	16:9	1.32 to 2.15	9.59 ft to 15.62 ft
Classroom short throw	100 in diagonal	16:10	0.48 to 0.65	3.39 ft to 4.59 ft
Large meeting hall	150 in diagonal	16:9	1.57 to 2.56	17.10 ft to 27.88 ft
Ultra short throw shelf	100 in diagonal	16:9	0.25 to 0.35	1.82 ft to 2.54 ft

Formula used

Screen width from diagonal: Width = Diagonal × aspect width ÷ √(aspect width² + aspect height²).

Screen height from diagonal: Height = Diagonal × aspect height ÷ √(aspect width² + aspect height²).

Throw distance range: Minimum distance = Width × minimum throw ratio. Maximum distance = Width × maximum throw ratio.

Required ratio for known distance: Required throw ratio = throw distance ÷ screen width.

Lens center estimate: Lens center = screen bottom + half screen height + vertical offset percent × screen height.

Brightness estimate: Foot-lamberts = projector lumens × screen gain ÷ screen area in square feet. Lux = lumens × gain ÷ area in square meters.

How to use this calculator

Enter the room name and choose the measurement unit used on site.
Select diagonal or width as the screen input basis.
Choose an aspect ratio, or enter a custom ratio.
Enter the minimum and maximum throw ratios from the Epson model manual.
Add a known throw distance if you want to test an existing mount point.
Enter screen bottom height, ceiling height, offset, and shift values.
Review the result above the form after pressing the submit button.
Download CSV or PDF notes for your construction file.

Planning Projection Distance on Site

A projector layout affects framing, cable routes, ceiling work, and final viewing comfort. Construction teams need more than a rough screen diagonal. They need working distances that respect the lens, wall height, screen position, and service clearance. This calculator keeps those items together, so a drawing can move from estimate to installation with fewer surprises.

Why Throw Ratio Matters

Throw ratio links image width to projector distance. A lower ratio places the unit closer to the screen. A higher ratio places it farther away. Many Epson style installations use zoom lenses, so the real answer is often a minimum and maximum distance, not one fixed point. That range helps the installer choose a joist bay, shelf depth, or ceiling bracket location.

Screen Geometry Comes First

The diagonal size alone is not enough. Aspect ratio changes the screen width and height. A 120 inch screen at 16:9 is wider than a 120 inch screen at 4:3. Since throw distance uses image width, the calculator first converts diagonal and ratio into exact width and height. It also accepts direct screen width when plans already include the final screen frame.

Mounting Checks

Projection distance is only one part of the build. Lens height, image offset, ceiling clearance, and side shift can decide whether the projector clears beams, lights, sprinklers, and ductwork. The tool estimates lens center height and horizontal side movement. These numbers are planning aids. Always compare them with the exact projector manual before drilling.

Brightness Review

Construction rooms differ. A training room may have daylight. A theater may be controlled. The brightness estimate uses lumens, screen gain, and screen area to produce foot-lamberts and lux. This helps compare layouts before equipment is ordered. It does not replace a lighting study, but it gives a useful first warning.

Better Field Notes

The CSV and PDF buttons make the result easy to share with clients, electricians, and ceiling installers. Save the output with the room name, selected ratio, and mounting notes. Then verify every dimension on site, including wall flatness, screen border size, bracket extension, and cable service loops. Record both metric and imperial values for mixed trade teams. This prevents quick conversion mistakes during coordination.

FAQs

Is this calculator only for Epson projectors?

It is designed for Epson planning, but it uses editable throw ratios. Enter the exact minimum and maximum ratio from your projector manual for the most accurate layout.

What is throw distance?

Throw distance is the distance from the projector lens to the screen surface. It changes with screen width, lens ratio, zoom range, and model settings.

Should I use diagonal or screen width?

Use diagonal when you only know the advertised screen size. Use width when the construction drawing already gives the finished image width.

Why does the result show a range?

Many lenses have zoom. The lower ratio gives the closest position. The higher ratio gives the farthest position that can still fill the image.

Can I use this before buying equipment?

Yes. It is useful for early room planning, cable routes, and mount locations. Always verify the final numbers with the exact Epson model data.

What does vertical offset mean?

Vertical offset estimates the lens center relative to the image center. Positive values move the lens center above the image center in this planner.

Are brightness results final engineering values?

No. They are estimates based on lumens, gain, and image area. Room lighting, screen material, projector mode, and lamp aging can change perceived brightness.

Why include CSV and PDF downloads?

They let installers share a quick record with clients, electricians, ceiling crews, and project managers without copying values by hand.