Convert luminance units — candela/m², nit, stilb, foot-lambert and more.
| Unit | Name | Value |
|---|---|---|
| cd/m² | Candela/Square Meter | 1550 |
| nt | Nit | 1550 |
| sb | Stilb | 0.155 |
| L | Lambert | 0.48694669 |
| fL | Foot-lambert | 452.38832 |
| cd/ft² | Candela/Square Foot | 143.99985 |
Formula: Nit = Candela/in² × 1550
Multiply any Candela/in² value by 1550 to get Nit.
Reverse: Candela/in² = Nit × 0.0006452
Common luminance values — factor: 1 cd/in² = 1550 nit
| Candela/in² (cd/in²) | Nit (nit) | Context |
|---|---|---|
| 0.0001 cd/in² | 0.155 nit | Dim |
| 0.001 cd/in² | 1.55 nit | Very dim |
| 0.01 cd/in² | 15.5 nit | 1 nit range |
| 0.1 cd/in² | 155 nit | 155 nit |
| 0.645 cd/in² | 999.8 nit | 1,000 nit HDR |
| 1 cd/in² | 1550 nit | 1,550 nit |
| 2 cd/in² | 3100 nit | 3,100 nit |
| 5 cd/in² | 7750 nit | 7,750 nit |
| 6.45 cd/in² | 9998 nit | 10,000 nit HUD |
| 10 cd/in² | 1.55e+04 nit | 15,500 nit |
| 64.5 cd/in² | 9.998e+04 nit | 100,000 nit |
| 100 cd/in² | 1.55e+05 nit | 155,000 nit |
| 645 cd/in² | 9.998e+05 nit | 1 Mnit |
| 1e+04 cd/in² | 1.55e+07 nit | 15.5 Mnit |
| 1e+06 cd/in² | 1.550e+09 nit | Very extreme |
1 cd/in² = 1550 nit.
nit = cd/m² exactly. Use this as the bridge between SI and legacy units.
Multiply result by 0.0006452 to recover the original cd/in² value.
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 inch (cd/in²) is used in display engineering and high-brightness projector specifications where cd/m² values would be inconveniently large. One cd/in² = 1,550 cd/m².
Very high-brightness applications use cd/in²: aviation cockpit displays, outdoor digital signage, and laser projectors for cinema and simulation. A 10,000 nit HDR display = 6.45 cd/in²; a cinema laser projector at 60,000 lumens might achieve 20+ cd/in² on a small screen.
Interesting fact: Military aircraft cockpit displays must remain readable in direct sunlight (approximately 10,000 cd/m² ambient). Modern night-vision-compatible displays adjust from <0.001 cd/in² (night mode) to >6 cd/in² (day mode) — a range of over 6 million to one.
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/in² = 1550 nit. Reverse: 1 nit = 0.0006452 cd/in².
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.