candelas per square metre (cd/m2) to nits (nt) conversion

1 cd/m2 = 1 ntnt → cd/m2
Formula
1 cd/m2 = 1 nt

Understanding candelas per square metre to nits Conversion

The candela per square metre (cd/m2) is the SI unit of luminance, and the nit (nt) is simply its trade name, used extensively in the display industry to quote screen and TV brightness. The two are identical: one nit is defined as exactly one candela per square metre. This "conversion" is therefore a straightforward renaming, useful mainly when a datasheet lists nits and a specification calls for cd/m2 or vice versa.

Conversion Formula

1 cd/m2=1 nt1\ \text{cd/m2} = 1\ \text{nt}

To convert candelas per square metre to nits, multiply by this factor:

nt=cd/m2×1\text{nt} = \text{cd/m2} \times 1

Step-by-Step Example

Convert 25 candelas per square metre to nits.

nt=25×1=25 nt\text{nt} = 25 \times 1 = 25\ \text{nt}

How to Convert candelas per square metre to nits

The two units are identical, so conversion is just relabeling.

  1. Note the luminance: Start with the value in cd/m2, for example 25.
  2. Apply the factor of 1: One nit equals one candela per square metre exactly.
  3. Keep the number: 25×1=2525 \times 1 = 25.
  4. State the result: 25 cd/m2 equal 25 nits.

candelas per square metre to nits conversion table

candelas per square metre (cd/m2)nits (nt)
00
11
22
33
44
55
66
77
88
99
1010
1515
2020
2525
3030
4040
5050
6060
7070
8080
9090
100100
150150
200200
250250
300300
400400
500500
600600
700700
800800
900900
10001000
20002000
30003000
40004000
50005000
1000010000
2500025000
5000050000
100000100000
250000250000
500000500000
10000001000000

What is the candela per square metre?

The candela per square metre is the SI unit of luminance, measuring the luminous intensity emitted or reflected from a surface per unit area in a given direction. It describes how bright a surface appears to the human eye and is the standard used to specify display and screen brightness.

Definition

Luminance is luminous intensity per unit projected area. One candela per square metre is the luminance of a surface emitting one candela of luminous intensity from each square metre of its projected area.

1 cd/m2=1 cd/m21\ \text{cd/m}^2 = 1\ \text{cd/m}^2

As a derived SI unit it can be written 1 cd/m2=1 lm/(m2⋅sr)1\ \text{cd/m}^2 = 1\ \text{lm}/(\text{m}^2 \cdot \text{sr}), since the candela equals one lumen per steradian.

Origin and History

The candela became one of the seven SI base units in 1948 (as the "new candle"), and luminance in candela per square metre followed as the coherent derived unit. It replaced a patchwork of earlier photometric units such as the stilb, lambert, and foot-lambert.

Law and Notable Facts

The candela per square metre is the internationally sanctioned SI unit of luminance and is colloquially known as the "nit." Its value ties to the modern definition of the candela, fixed by the luminous efficacy of monochromatic 540 THz radiation at 683 lm/W.

Real-World Examples and Conversions

  • A typical computer monitor: 200–350 cd/m².
  • A smartphone in bright sunlight mode: 800–2000 cd/m².
  • Clear daytime sky: several thousand cd/m².
  • 1 cd/m2=1 nit=10−4 stilb1\ \text{cd/m}^2 = 1\ \text{nit} = 10⁻⁴\ \text{stilb}.

What is the nit?

The nit is a unit of luminance used to describe the brightness of light emitted from or reflected by a surface, most familiarly the screens of televisions, monitors, and phones. It is numerically identical to the SI unit, the candela per square metre.

Definition

One nit is exactly one candela per square metre, the luminous intensity of one candela spread over one square metre of projected surface area.

1 nt=1 cd/m21\ \text{nt} = 1\ \text{cd/m}^2

The two units are interchangeable: 1 nt=1 cd/m2=1 lm/(m2⋅sr)1\ \text{nt} = 1\ \text{cd/m}^2 = 1\ \text{lm}/(\text{m}^2 \cdot \text{sr}).

Origin and History

The name "nit" derives from the Latin nitere, meaning "to shine," and came into use in the mid-20th century as a convenient shorthand for the candela per square metre. It remains popular in the display and photometry industries.

Law and Notable Facts

The nit is not an official SI unit name but is exactly equal to the SI candela per square metre, so it carries no ambiguity. Display manufacturers routinely quote peak brightness in nits, with high-dynamic-range (HDR) televisions marketed at 1000 nits or more.

Real-World Examples and Conversions

  • Standard SDR television: about 100 nits reference white.
  • Modern OLED and LCD monitors: 250–600 nits.
  • HDR displays: peak highlights of 1000–4000 nits.
  • 1 nt=1 cd/m2=10−4 stilb≈3.14159 apostilbs1\ \text{nt} = 1\ \text{cd/m}^2 = 10⁻⁴\ \text{stilb} \approx 3.14159\ \text{apostilbs}.

Frequently Asked Questions

Are candelas per square metre and nits the same thing?

Yes. One nit is defined as exactly one candela per square metre, so the conversion factor is 1 and no calculation is needed.

Why do two names exist for the same unit?

"Candela per square metre" is the formal SI name, while "nit" is a shorter trade term (from Latin nitere, to shine) popular in the display and TV industry for convenience.

Do I need to convert nits before comparing screen brightness?

No. A screen rated at 400 nits is identical to 400 cd/m2, so figures can be compared directly regardless of which label a manufacturer prints.

What are typical nit values for displays?

Indoor monitors are often 250–350 nits, mainstream TVs 300–500 nits, and HDR displays can reach 1000 nits or more; each figure is also its cd/m2 value.

What is 25 cd/m2 in nits?

Exactly 25 nits, since the units are equal; 25 nits is quite dim, similar to a screen at a low nighttime brightness setting.

People also convert

cd/m2 to sbcd/m2 to asbcd/m2 to Lcd/m2 to fL

Complete candelas per square metre conversion table

cd/m2
UnitResult
nits (nt)1 nt
stilbs (sb)0.0001 sb
apostilbs (asb)3.141593 asb
lamberts (L)0.0003141593 L
foot-lamberts (fL)0.2918635 fL

Luminance conversions