Luminance Converter
Convert between luminance units including cd/m², nit, foot-lambert, and stilb.
| Unit | Per cd/m² |
|---|---|
| Candela/m² (cd/m²) — nit | 1.0000e+0 |
| Nit (nt) | 1.0000e+0 |
| Foot-lambert (fL) | 3.4263e+0 |
| Stilb (sb) | 1.0000e+4 |
| Apostilb (asb) | 3.1831e-1 |
| Lambert (L) | 3.1831e+3 |
| Millilambert (mL) | 3.1831e+0 |
| Skot (sk) | 3.1831e-4 |
| Hefnerkerze/m² (Hk/m²) | 9.0300e-1 |
About this tool
Luminance is a measure of light intensity as perceived from a specific direction, and it's essential in fields like display technology, cinematography, lighting design, and visual perception research. Different industries use different units to quantify luminance—cd/m² (candelas per square meter) is the SI standard used in most technical fields, while nit is its equivalent commonly found in display specifications. Understanding and converting between luminance units is crucial for professionals who work with displays, projectors, cameras, or lighting systems.
This converter allows you to instantly transform luminance values between cd/m², nit, foot-lambert, and stilb. Enter your value in any unit, select the source and target units, and the tool calculates the equivalent instantly. It's useful for comparing display brightness specifications across manufacturers, verifying lighting levels in cinematography workflows, or adapting technical documentation from one standard to another across international projects.
The tool handles the precise mathematical relationships between each unit: 1 nit equals 1 cd/m², 1 foot-lambert equals approximately 3.426 cd/m², and 1 stilb equals 10,000 cd/m². Whether you're a display engineer, cinematographer, lighting designer, or researcher working with international equipment specifications, this converter eliminates manual calculation errors and saves time when moving between regional or discipline-specific standards.
Frequently Asked Questions
Code Implementation
# Luminance unit conversions (base unit: cd/m²)
LUMINANCE_TO_CD_M2 = {
"cd/m2": 1,
"nit": 1, # 1 nit = 1 cd/m²
"fL": 3.42625, # foot-lambert
"sb": 10000, # stilb
"asb": 1 / 3.14159, # apostilb
"L": 10000 / 3.14159, # lambert
"mL": 10 / 3.14159, # millilambert
"skot": 1e-3 / 3.14159, # skot
}
def convert_luminance(value: float, from_unit: str, to_unit: str) -> float:
cd_m2 = value * LUMINANCE_TO_CD_M2[from_unit]
return cd_m2 / LUMINANCE_TO_CD_M2[to_unit]
# Examples
print(f"1 fL = {convert_luminance(1, 'fL', 'cd/m2'):.4f} cd/m²")
print(f"1 sb = {convert_luminance(1, 'sb', 'cd/m2'):.0f} cd/m²")
print(f"300 nit = {convert_luminance(300, 'nit', 'fL'):.2f} fL")Comments & Feedback
Comments are powered by Giscus. Sign in with GitHub to leave a comment.