Lumens explained: how much light do you actually need?

Around 100 lumens for close work, 300 for a room, 1,000 for distance.

Lumens measure total light output, not how far a beam reaches or how useful it is. More is not automatically better: a very bright light in a confined space is worse than a moderate one, because everything beyond the beam becomes darker by contrast and your eyes never adapt.

As rough working figures: 20 to 100 lumens is plenty for reading a meter, finding something in a closet or walking a path. 100 to 300 covers most practical work such as looking under a sink or into an engine bay. 300 to 1,000 lights a room or a work area during a power cut. Above 1,000 is about throwing light a long way outdoors.

Two specifications matter more than peak lumens. Beam distance tells you how far the light is usable rather than merely visible. Runtime tells you how long it holds that output, and many lights quote a headline figure they sustain for only a couple of minutes before stepping down to protect the emitter. A light that gives 250 lumens for six hours is more useful in a power cut than one that gives 1,000 for twenty minutes.

Part of the Stalwart guides. See all guides.