How many lumens is a watt? How many lumens do I need for reading? What is as bright as a 100W bulb? We constantly get questions like that from our clients. The first question of course has no answer, since it is like comparing apples to oranges, but it shows the depth of confusion that is prevalent as the lighting industry is moving away from incandescent lighting.
We are all familiar with the good old light bulb and have a feel for how many watt we used for a specific task or location. We had a 150W 3-way bulb in our reading lamp and a 40-60W bulb in our wall sconce and one or two 150W bulb in our torchiere. Now most of these lamps (lighting lingo for light bulbs) are no longer available and the descriptions on the LED boxes talks about lumens.
Watts measure the amount of energy that is required to produce light, whereas lumens measure the amount of light that is emitted from a source.
Here is a comparison chart that is helpful for choosing your lamps or LEDs.