Luminance Converter

Convert between candela, lux, foot-candles, and other light measurement units

About Luminance Converter

Understanding Light Measurement

Light measurement involves several distinct but related quantities. The candela (cd), the SI base unit for luminous intensity, measures the power of light in a particular direction. From this foundation, we derive other important units: the lumen (lm) for total light output, the lux (lx) for illuminance, and various units for luminance (brightness). These measurements are crucial in lighting design, photography, display technology, and architectural planning.

Common Light Levels

Condition	Illuminance	Description
Full Sunlight	100,000 lx	Direct sun
Daylight	10,000-20,000 lx	Overcast day
Office Lighting	300-500 lx	Typical workspace
Street Lighting	10-20 lx	Night safety

Unit Categories

Luminous Intensity & Flux

Candela (cd): Light intensity
Lumen (lm): Total light output
1 lm = 1 cd × sr (steradian)
LED efficiency: 100-200 lm/W

Illuminance & Luminance

Lux (lx): Light per area
Foot-candle (fc): US unit
Nit (cd/m²): Screen brightness
1 fc = 10.764 lx

Applications

Professional Uses

Architectural lighting design
Photography and cinematography
Display calibration
Workplace safety standards
Scientific research

Display Technology

HDR displays: 1,000+ nits
OLED phones: 400-800 nits
LCD monitors: 200-350 nits
HDR TVs: up to 2,000 nits

Learn More

IES Standards