The candela per square metre (cd/m) is the derived SI unit of luminance. The unit is based on the candela, the SI unit of luminous intensity, and the square metre, the SI unit of area.

As a measure of light emitted per unit area, this unit is frequently used to specify the brightness of a display device. Most consumer desktop liquid crystal displays have luminances of 200 to 300 cd/m; the sRGB spec for monitors targets 80 cd/m. High-definition televisions range from 450 to about 1000 cd/m. Typically, calibrated monitors should have a brightness of 120 cd/m.