The beam angle of an LED bulb is the angular dimension of the cone of light from the lamp. It encompasses the central part of the beam out to the angle where the intensity is 50 percent of maximum.
For most household ceiling fitted applications, a beam angle of 30 or 40 degrees would be sufficient. For outdoor applications, a wider beam angle of 60 to 120 degrees is preferred to cover a larger surface area.
Color temperatures range from warm white to cool white.
The numerical value represents the diameter of the bulb in 1/8 of an inch. Typical sizes include PAR16, PAR20, PAR30, PAR30 long neck, and PAR38.
Common measurements:
PAR floodlights have a flat lens and are available in an assortment of beam angles.
BR (Bulged Reflector) floodlights have a curved lens that have a wide flood beam angle, over 45 degrees.