Recessed Lighting Calculator
How many recessed lights to sketch on a grid — not a lighting design. Click any i for detail.
Room
Length (ft)
i
Length
Long wall of the room. |
|
|---|---|
Width (ft)
i
Width
Short wall of the room. |
|
Spacing (ft)
i
Spacing
On-center spacing. A common sketch is ~½ the ceiling height, often 4–6 ft. |
How to use this calculator
- Enter room length and width.
- Set a target on-center spacing.
- Read the rounded grid (along × across).
- Have a licensed electrician confirm IC-rated cans, circuits, and dimming.
Results explained
Cans along each axis ≈ round(dimension ÷ spacing), at least 1. Total = along × across. Edge offset is often ~½ spacing from the wall. Not a lumen or energy-code check.
Quick reference: recessed layout
Aim for even spacing more than a magic can count.
| Item | Detail |
|---|---|
| 8-ft ceiling (rule of thumb) | ~4 ft spacing sketch |
| 9–10 ft ceiling | Often 5–6 ft |
| 16×12 room @ 6 ft | 3 × 2 = 6 cans on this page |
| Switch loops / 3-way | Not modeled |
Kitchen task lighting and wall-wash art lights use different aiming than a uniform grid.
How the estimate is built
along = max(1, round(L / spacing)); across = max(1, round(W / spacing)); cans = along × across.
Example scenario
16×12 ft at 6 ft spacing → 3 × 2 = 6 suggested cans.
FAQ
Is this the NEC?
No. Circuit loading, IC vs non-IC, and insulation contact are electrician questions.
Wafer vs can?
Count is the same idea; housing type is a product choice.
High hats over a table?
You may want a different layout than a full-room grid.