Recessed Lighting Calculator
How many recessed lights a room needs for its use — with the total lumens and an even spacing — so it's neither cave-dark nor airport-bright.
FAQ
- How many recessed lights do I need?
- Multiply the room area by the target brightness for its use (in foot-candles), which gives the total lumens needed, then divide by the lumen output of one fixture. A kitchen or office needs roughly double the brightness of a bedroom or hallway.
- How far apart should recessed lights be?
- The calculator suggests a center-to-center spacing that distributes the fixtures evenly across the floor. A common rule of thumb is to space them about half the ceiling height apart — closer for task areas, wider for ambient fill.
- Does this replace task and accent lighting?
- No — it sizes the ambient (general) layer. Good rooms layer light: ambient recessed for overall level, task lighting where you work, and accent lighting for depth. Put everything on dimmers so one room can do bright work and low evening light.
Rooms you can plan with this tool
Real-room inspiration that uses this tool's outputs.
bathroom
Coastal bathroom — board-and-batten, white tile, brushed brass done right
coastal, traditional
kitchen
Farmhouse kitchen — shaker cabinets, soapstone, exposed beams done correctly
farmhouse, traditional
bathroom
Japandi bathroom — river stone, white oak, matte black done correctly
japandi, minimalist