Physics

Estimate shop light count, work-surface brightness, fixture layout, spacing, power use, and weekly energy cost.

Estimate stairwell lumens, fixture count, foot-candles, and yearly energy cost from tread area, landings, and fixture output.

Estimate hallway fixture count, lumens per fixture, spacing, light level, and LED watts from hallway size and fixture lumens.

Estimate closet lumens, fixture count, brightness, energy cost, and basic clearance for common closet light types.

Estimate basement light count, lumens, rows, spacing, wall offsets, foot-candles, and optional energy use.

Estimate dining room fixture lumens, fixture width, linear length, and hanging height from room and table size.

Estimate living room lumens, bulb count, installed light, extra light, and LED watts from room size and brightness goal.

Estimate bedroom lumens, light count, LED watts, foot-candles, and lux from room size, goal, and lumens per light.

Estimate security light coverage or lumens needed using area, foot-candles, losses, height, and beam angle.

Estimate floodlight coverage from lumens, beam angle, mounting height, light loss, overlap, and target foot-candles.