Amit's data tools
LuxPlan
625 sq ft · 300 lux target

25×25 kitchen:
40 lights

40 fixtures A 25×25 ft kitchen (625 sq ft) needs approximately 40 recessed lights at 800 lumens each — about 30,321 lumens in total — laid out 5 across by 8 deep.

Space them 5 ft apart along the 25 ft wall and 3.1 ft apart along the 25 ft wall, starting 2.5 ft from the end walls.

Fixtures40at 800 lm each
Total lumens30,321to hit 300 lux
Spacing5′× 3.1′ apart
Wall offset2.5′from the end wall

The ceiling plan

Drawn to scale, with each fixture at its computed position and the pale circles showing roughly where each one lands on the working plane.

25 ft 25 ft 5 across × 8 deep · 5 ft × 3.1 ft apart · 2.5 ft from the end walls

Same room, different fixtures

If you have already chosen a fitting, read across from its lumen output.

Fixture outputRough equivalentFixtures neededSuggested grid
450 lm 40 W incandescent 7010 × 7
650 lm 50 W incandescent 497 × 7
800 lm 60 W incandescent 405 × 8
1000 lm 75 W incandescent 305 × 6
1200 lm 100 W incandescent 255 × 5

Fewer, brighter fixtures give more contrast; more, dimmer fixtures give flatter, more even light. Both rows deliver the same total.

How the 40 was calculated

Target illuminance for a kitchen300 luxpublished range 300–500 lux
Floor area58.1 m²625 sq ft
Mounting height above the working plane5 ft8 ft ceiling, 3.0 ft working plane
Room index2.48(L × W) ÷ (Hm × (L + W))
Utilisation factor0.72from the room index, light surfaces
Maintenance factor0.8dirt and lamp depreciation
Lumens required30,321 lm300 × 58.1 ÷ (0.72 × 0.8)
Fixtures at 800 lm40delivering about 317 lux

Worktops are the critical surface, so a kitchen needs roughly double a living room. Under-cabinet lighting handles the task layer; ceiling fixtures handle the rest.

Other ceiling heights

CeilingFixturesGridSpacingMax spacing
8 ft405 × 85′ × 3.1′6.6′
9 ft426 × 74.2′ × 3.6′7.9′
10 ft426 × 74.2′ × 3.6′9.2′
12 ft486 × 84.2′ × 3.1′11.8′

Questions

How many recessed lights do I need for a 25x25 kitchen?

About 40 fixtures at 800 lumens each, arranged 5 across by 8 deep. That gives roughly 317 lux across 625 square feet, against a target of 300 lux for a kitchen.

How many lumens does a 25x25 kitchen need?

Roughly 30,321 lumens in total. That comes from 300 lux over 58.1 m², divided by a utilisation factor of 0.72 and a maintenance factor of 0.8 — the light that never reaches the working plane has to be paid for up front.

How far apart should the lights be in a 25x25 room?

5 ft apart along the 25 ft wall and 3.1 ft apart along the 25 ft wall, with the outer row about 2.5 ft in from the end walls — half a spacing. With a 8 ft ceiling the maximum sensible spacing is around 6.6 ft before the floor starts to show scallops.

Does the ceiling height change the answer?

Yes, in two ways. A higher ceiling spreads each fixture's light over a wider area, so fixtures can sit further apart — but it also drops the light level reaching the floor, so a taller room generally needs more total lumens. At 8 ft the room index works out at 2.48, giving a utilisation factor of 0.72.

Computed with the lumen method — see how it works and where it is weak. Planning guidance only, not an electrical design. Fixture counts are a starting point — follow your local wiring rules and use a licensed electrician for the installation.

One family of free data tools