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Since LEDs replaced incandescent bulbs, watts no longer tell you how bright a light is — lumens do. Enter your room’s size and use to see how many lumens you need and how many bulbs that works out to.
How it works
Light on a surface is measured in foot-candles (lumens per square foot) or lux (lumens per square meter; 1 foot-candle = 10.76 lux). Multiply the room’s area by the recommended foot-candles for its use to get the total lumens needed. Our ranges follow typical residential recommendations based on Illuminating Engineering Society guidance.
| Room | Foot-candles | Lux | Lumens for 150 sq ft |
|---|---|---|---|
| Living room, bedroom | 10–20 | 108–215 | 1,500–3,000 |
| Hallway, stairs | 5–10 | 54–108 | 750–1,500 |
| Dining room, kitchen (general) | 30–40 | 323–431 | 4,500–6,000 |
| Home office | 30–50 | 323–538 | 4,500–7,500 |
| Bathroom, kitchen counters | 70–80 | 753–861 | 10,500–12,000 |
LED bulb brightness guide
| Old incandescent | LED lumens | Typical LED watts |
|---|---|---|
| 40 W | 450 | 5–6 W |
| 60 W | 800 | 8–10 W |
| 75 W | 1,100 | 11–13 W |
| 100 W | 1,600 | 15–18 W |
FAQ
Why do bathroom and counter numbers seem so high?
They’re task areas — shaving, makeup, chopping — where you need bright, shadow-free light on a small surface. You don’t need that level across the whole room; under-cabinet lights and vanity lights provide it where it’s needed.
What color temperature should I choose?
2700–3000 K (warm white) for living areas and bedrooms, 3500–4000 K for kitchens and offices, and 5000 K for garages and workshops.
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