Lighting Calculator
Enter your room's dimensions and select its type to find the recommended total lumens and LED wattage.
Wattage estimate assumes LED lighting at roughly 80 lumens per watt.
How lighting needs are calculated
Total lumens needed is estimated by multiplying a room's floor area by a recommended brightness level in foot-candles, which varies by room type — task-focused spaces like kitchens and bathrooms need more light than relaxation spaces like living rooms and bedrooms.
The wattage estimate converts lumens to watts using LED efficacy (lumens produced per watt consumed), roughly 80 lm/W for typical modern LED bulbs. Older incandescent or halogen bulbs are far less efficient and would need several times this wattage for the same brightness.
Frequently asked questions
Why do different rooms need different brightness levels?
Task-oriented spaces like kitchens and bathrooms benefit from brighter, more even lighting for safety and precision (like cooking or shaving), while living rooms and bedrooms are typically lit more softly for comfort and relaxation.
Should this lumen total come from a single light fixture?
Not necessarily — the total is usually split across multiple fixtures (ceiling lights, lamps, under-cabinet lighting) to distribute light evenly and avoid harsh shadows, rather than coming from one single very bright source.
Does the wattage change if I use incandescent bulbs instead of LED?
Yes, significantly — incandescent bulbs produce roughly 10-17 lumens per watt versus an LED's 80+, so you'd need 5-8 times the wattage shown here to achieve the same total brightness with incandescent bulbs.