Convert luminance units — candela/m², nit, stilb, foot-lambert and more.
| Unit | Name | Value |
|---|---|---|
| nt | Nit | 1 |
| sb | Stilb | 0.0001 |
| L | Lambert | 0.00031415915 |
| fL | Foot-lambert | 0.29186343 |
| cd/ft² | Candela/Square Foot | 0.09290313 |
| cd/in² | Candela/Square Inch | 0.00064516129 |
Formula: Nit = Candela/m² × 1
Multiply any Candela/m² value by 1 to get Nit.
Reverse: Candela/m² = Nit × 1
Common luminance values — factor: 1 cd/m² = 1 nit
| Candela/m² (cd/m²) | Nit (nit) | Context |
|---|---|---|
| 0.001 cd/m² | 0.001 nit | Moonlit night sky |
| 0.1 cd/m² | 0.1 nit | Overcast sky |
| 1 cd/m² | 1 nit | Candle flame |
| 10 cd/m² | 10 nit | Very dim display |
| 50 cd/m² | 50 nit | Dark room display |
| 100 cd/m² | 100 nit | SDR reference white |
| 200 cd/m² | 200 nit | Typical office monitor |
| 500 cd/m² | 500 nit | Bright monitor |
| 1000 cd/m² | 1000 nit | HDR10 peak |
| 2000 cd/m² | 2000 nit | iPhone peak outdoor |
| 5000 cd/m² | 5000 nit | Dolby Vision phone |
| 1e+04 cd/m² | 1e+04 nit | Automotive HUD |
| 1e+05 cd/m² | 1e+05 nit | Direct sunlight |
| 1e+06 cd/m² | 1e+06 nit | Arc lamp |
| 1.600e+09 cd/m² | 1.600e+09 nit | Sun surface |
cd/m² = nit. They are identical.
No calculation needed — just change the label.
Nit is dominant in consumer electronics; cd/m² in scientific and lighting contexts.
Specifies monitor, TV, and smartphone panel brightness in nits (cd/m²) for HDR grading and product specs.
Calibrates projector output to SMPTE standard of 14 foot-Lamberts for optimal image quality.
Calculates luminance of illuminated surfaces in cd/m² to evaluate glare and visual comfort.
Designs head-up displays exceeding 10,000 nits for daylight readability.
Converts between legacy (Lambert, stilb) and SI (cd/m²) units when reviewing historical data.
Specifies outdoor LED sign brightness in nits for visibility across ambient lighting conditions.
Candela per square meter (cd/m²) is the SI unit of luminance, measuring the intensity of light emitted from a surface per unit area per steradian. It is identical to the nit (nt) in value and replaced the older photometric units in the International System of Units adopted in 1979.
cd/m² is the universal unit in display technology and lighting engineering. Computer monitors: 200–350 cd/m²; smartphone screens: 600–2,000 cd/m²; the sun's surface: about 1.6 × 10⁹ cd/m². SDR content is mastered at 100 cd/m²; HDR10 peaks at 1,000–10,000 cd/m².
Interesting fact: The minimum luminance the human eye can detect is about 10⁻⁶ cd/m² (starlight). The maximum comfortable luminance for sustained viewing is about 1,000 cd/m². The Sun at midday has a luminance of approximately 1.6 billion cd/m².
The nit (nt) is a non-SI unit of luminance equal to one candela per square meter (cd/m²). The name comes from the Latin nitere (to shine). While not part of the official SI system, it is universally used in the display industry.
Consumer electronics specifications universally use nits: OLED TVs peak at 1,000–2,000 nits for HDR; iPhone 15 Pro reaches 2,000 nits peak outdoor brightness; automotive head-up displays require 10,000+ nits for daylight visibility.
Interesting fact: The Apple Vision Pro headset achieves 5,000 nits in its micro-OLED displays — brighter than nearly any other consumer display. The standard for 'very bright' smartphone screens has escalated from 500 nits (2015) to 2,000+ nits (2024) due to outdoor usability demands.
Luminance measures how bright a surface appears to a human observer. The SI unit is cd/m² (identical to the nit used in display industry). Older units — Lambert, foot-Lambert, and stilb — remain in cinema, photometry, and legacy specs. Key anchors: 100 cd/m² = SDR reference; 1,000 cd/m² = HDR10 peak; 14 fL = 48 cd/m² = SMPTE cinema standard.
Exact factor: 1 cd/m² = 1 nit. Reverse: 1 nit = 1 cd/m².
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.