Lux

Updated: 10/01/2023 by Computer Hope

The lux is the measurement of light output, often measured using a lux meter. More specifically, one lux equals one lumen per square meter. The symbol for lux is lx. Below are examples of different illuminance levels under different lighting conditions and their lux values.

Examples levels of illuminance

Lighting condition Candles Lux
Sunlight 10,000 107,527
Full daylight 1,000 10,752
Overcast day 100 1,075
Very dark day 10 107
Twilight 1 10.8
Deep twilight 0.1 1.08
Full moon 0.01 0.108
Quarter moon 0.001 0.0108
Starlight 0.0001 0.0011
Overcast night 0.00001 0.0001

Candle, Display terms, Illuminance, Measurements, SI