Convert luminance units — candela/m², nit, stilb, foot-lambert and more.
| Unit | Name | Value |
|---|---|---|
| cd/m² | Candela/Square Meter | 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: Stilb = Nit × 0.0001
Multiply any Nit value by 0.0001 to get Stilb.
Reverse: Nit = Stilb × 1e+04
Common luminance values — factor: 1 nit = 0.0001 sb
| Nit (nit) | Stilb (sb) | Context |
|---|---|---|
| 0.001 nit | 1.000e-07 sb | Moonlit sky |
| 0.1 nit | 1.000e-05 sb | Overcast sky |
| 1 nit | 0.0001 sb | Candle |
| 10 nit | 0.001 sb | Dim display |
| 50 nit | 0.005 sb | Dark room |
| 100 nit | 0.01 sb | SDR standard |
| 200 nit | 0.02 sb | Office monitor |
| 500 nit | 0.05 sb | Bright screen |
| 1000 nit | 0.1 sb | HDR10 peak |
| 2000 nit | 0.2 sb | Peak outdoor phone |
| 5000 nit | 0.5 sb | Top-tier HDR |
| 1e+04 nit | 1 sb | HUD daylight |
| 1e+05 nit | 10 sb | Direct sunlight |
| 1e+06 nit | 100 sb | Arc lamp |
| 1.600e+09 nit | 1.6e+05 sb | Sun surface |
nit ÷ 10,000 = sb. Exactly.
10,000 nit = 1 sb. 1,000 nit = 0.1 sb.
sb × 10,000 = nit.
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.
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.
The stilb (sb) is the CGS unit of luminance, equal to 1 candela per square centimeter = 10,000 cd/m². The name comes from the Greek stilbein (to glitter). It was defined in the CGS system in 1918 and predates SI luminance units.
Stilbs are found in older scientific and photometric literature, particularly pre-1970s publications on arc lamps, flashtubes, and laser beam characterization. A carbon arc lamp produces about 15,000 sb (150 million cd/m²).
Interesting fact: The term 'stilb' is rarely used in modern practice outside of historical photometry and some laser physics contexts. The sun's surface luminance of ~2 × 10⁵ sb (2 billion cd/m²) was historically expressed in stilbs in astrophysics literature.
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 nit = 0.0001 sb. Reverse: 1 sb = 1e+04 nit.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.