What are Lumens

Lumens = Light Output. Lumens (lm) is the metric measurement of light output and it is an extremely important consideration to understand with regard to LED ( or any light source ). The imperial equivalent to lumens is Candella (cd) there is a difference in the explanation of both in that Lumens refers to the total amount of light emitted by a lighting apparatus. The higher the lumens value of a lighting device, the greater is the area lighted up by it. On the other hand, candela refers to the amount of light emitted by a lighting device in a particular direction. We won’t go down this rabbit hole just yet as it’s not necessary to know the exact ins and outs unless you are a light engineer. For now, just understand that the higher the lumen output rating the brighter the light will be.
Watts and Lumens

Lumens is not quite part of our vocabulary as much as watts are. I am sure we have all experienced running to the store to buy a light for our house that just went out. What is the only metric we used? I would be willing to bet that its watts. This no longer applies to the world of LED. You see watts are the unit of energy that is used to light the bulb, with incandescent the higher the wattage the brighter the bulb shines. LEDs are by their very nature very low on energy consumption but high on light output. This means we need to look at what we buy now in terms of lumen output and not energy consumed ( wattage ) Remember more light with less energy.
Lumens per Watt

As you can see LEDs are in a different league when it comes to lumens output for wattage used. The next time you look to buy your lights as the right question, there are a lot of different ways to look at lighting options but lumen output is a great way to start.