Recessed Lighting Calculator
Calculate optimal downlight spacing and positioning for any room size.
How to use the Recessed Lighting Calculator
- Enter the room length, width and ceiling height in feet.
- Select the room type to start from an appropriate target light level.
- Choose the recessed light output and beam angle from the product data.
- Review the suggested grid, wall offsets and fixture spacing in feet.
Why use this tool
- Provides a consistent starting grid instead of spacing fixtures by eye.
- Shows wall offsets and spacing in US customary measurements.
- Lets you compare layouts for different room uses, beam angles and fixture outputs.
A layout estimate is only a starting point. Actual illumination depends on lumens, beam distribution, ceiling height, surface colors, daylight and the tasks performed in the room. Confirm the fixture photometric data, wet or damp location rating, insulation-contact rating, clearances, dimmer compatibility and the electrical code adopted by the project jurisdiction. A licensed electrical professional should verify the circuit and installation where required.
Part of Builder Tools Calculators — construction tools for US contractors.