A spotlight’s beam angle is one of its most important characteristics, yet often one of the most commonly overlooked.
In short, a light bulb’s beam angle denotes how wide its light spreads. It is measured in degrees, and the bigger the number, the wider the beam of light.
Different beam angles are better for certain uses. For example, a retailer might need a spotlight with a very narrow, focused beam in order to show off products on a shop-floor display. A spotlight with a beam angle of 15-20° would be ideal in this instance.
Such a narrow beam would be no good, however, for someone who just wanted to light their kitchen. It would be highlight specific areas, such as the sink or a certain counter-top, very well, but it would leave much of the room in the dark. In this case, a spotlight with a much wider beam would be more suitable.
This can sometimes be hard to visualise without examples, so use our interactive switches below to see how spotlights with different beam angles illuminate a room.
You can find spotlights with beam angles anywhere between 15-110°. If you’re looking for light bulbs just to use for general lighting purposes, those at the higher end of the scale are ideal.
You may also find other types of light bulbs and fittings that specify a beam angle. Anything that is referred to as a directional light source (a lamp emits light in a specific direction, rather than all directions) should be labelled with its beam angle. Fluorescent tubes, surface mounted bulkheads and integrated downlights all fall into this category.
The principle is exactly the same in all these cases; the bigger the beam angle, the wider the light spread.