What is the difference between High Bay and Low Bay lights?

The main difference comes down to mounting height and how the light needs to be distributed. High bay lights are for ceilings 20 feet and up—often 40 to 50 feet. At that height, you need a narrow beam angle (like 60° to 90°) and high lumen output to punch light all the way down to the floor. Think warehouses, aircraft hangars, or big-box retail. Low bay lights are for ceilings under 20 feet, typically 12 to 18 feet. Because the fixture sits closer to the work plane, you use a wider beam (100° to 120°) to spread light evenly without creating a blinding hot spot right underneath.

That shape difference changes the fixture design too. High bays often use lenses or reflectors that focus the light—UFO-style or linear high bays with acrylic prisms. Low bays usually have a diffused lens or a broader reflector to kill harsh shadows and keep the floor uniformly lit. Wattage follows the same logic: a high bay might run 200W to 400W LED, while a low bay does 80W to 150W. Grab the wrong one, and a high bay on a low ceiling will blind everyone with a narrow cone of light; a low bay up high won't reach the floor.