What are lumens?

Lumens (lm) are a measure of the amount of visible light that a lamp emits. It is used to determine the brightness of a light (unlike a light’s wattage, which has no direct relation to its brightness). A typical bulb for use around the home might have a lumens output between 300-500lm, while high-powered floodlights can have a lumens output in excess of 20,000lm.