Lighting · Tool · 5 min ·
Watts used to tell you how bright a bulb was; with LEDs, the number to read is the lumen. A room needs a total, and a handy way to find it is lumens per square metre of floor, with more for a kitchen than a bedroom.
Pick a room, enter its size, light it with bulbs of different brightness, and tap the plan to place them. A bar shows whether you are under, inside or over the range. Plus when to break it, and what to measure before you buy.
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A plain warm-white E27 bulb for a lamp or fitting that is not on a dimmer. Check the lumen figure on the pack against the total you worked out, and that the cap matches your socket.
E27 · Warm white · 8.5 W
A dimmable warm-white bulb of about 800 lm, the classic 60 W size. Dimmable means you can aim for the top of a room's range and turn it down, but check the maker's dimmer compatibility list first.
E27 · 2700 K · 806 lm · Dimmable
A smart warm-white pair that dims from 40 to 810 lm through an app, so one bulb can suit reading and evening. You need the maker's app, and a bridge for remote control and routines.
E27 · 2700 K · 810 lm · App dimming
