When shopping for bulbs, you're probably accustomed to looking for watts, an indication of how bright the bulb will be. The brightness of LEDs, however, is determined a little differently.
Contrary to common belief, wattage isn't an indication of brightness, but a measurement of how much energy the bulb draws. For incandescents, there is an accepted correlation between the watts drawn and the brightness, but for LEDs, watts aren't a great predictor of how bright the bulb will be.
The point, after all, is that they draw less energy