Shoppers of LED light bulbs often ask how much heat is generated by LED bulbs in comparison with incandescent or halogen bulbs. Contrary to some marketing claims, LED bulbs do indeed generate heat as does anything that consumes electricity. The important thing to keep in mind is that LEDs consume a lot less energy than incandescent or halogen bulbs and are much more efficient in how they use that energy versus traditional bulb types.
Thus while LEDs will generate heat, it will be a fraction of that compared to a traditional technology bulb. The ultimate temperature at which the external housing of the LED will operate at is influenced by the temperature of the room and the fixture it is placed in.
LED bulbs have many components inside to change the high voltage electricity from your home or building to the lower voltage that the LED chips need to run. Because of this, they are much more sensitive to heat than incandescent or halogen sources. You will frequently find that many low cost LED bulbs carry a warning that they should not be placed in fully enclosed fixtures. The reason for this is that this heat build up can shorten the life of the components inside of the LED bulb. Only use fully enclosed rated LED bulbs in fixtures of this type or you may void the warranty.
Overall though, the lower heat generated by LEDs makes them a great choice for applications such as task lighting and illumination of heat sensitive objects such as food or artwork that can be damaged by heat.
Watch the video below for a fun demonstration of the differences in heat output between incandescent and LED light sources: