How Many Lumens Do You Need Per Room? A Room-by-Room Guide for US Homes

Stop asking “what wattage?” Ask “how many lumens?”

Watts measure power, not brightness. Brightness is lumens. If you are still buying “60W equivalent,” you are guessing.

For ambient light in a US home, plan around 10-20 lumens per square foot for relaxed spaces and 30-50+ for task spaces. A 120 sq ft living room needs roughly 1,200-2,400 total lumens. A kitchen of the same size needs 4,000-8,000 lumens because counters need task light on top of ambient.

Use this quick map: bedroom 1,500-3,000 lm total; living room 2,000-4,000 lm; kitchen 4,000-8,000 lm; bathroom mirror area 1,600-2,400 lm; home office 3,000-6,000 lm. Dark walls, high ceilings, or opaque shades push you toward the high end.

Action: measure your room’s length and width, multiply for square feet, then multiply by the lumens-per-foot target. Divide by the number of fixtures or lamps to get the lumen rating each bulb needs.