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Luminance Converter

Convert surface brightness and monitor luminance across Candela per square meter (cd/m²), Nits, and Foot-lamberts (fL) with real-time bidirectional calculations.

Explore Luminance Guide & Formulas↓View Luminance Converter Chart→
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Simultaneous Category Equivalents

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Popular Luminance Conversion Shortcuts

Instant pair conversions with verified scientific and mathematical formulas

Quick Pairs
Nits to cd/m²→
1 Nit = 1 cd/m² (Exact)
cd/m² to Nits→
1 cd/m² = 1 Nit (Exact)
Nits to Foot-lamberts→
1 Nit = 0.29186 fL
Foot-lamberts to Nits→
1 fL = 3.42626 Nits
cd/m² to Foot-lamberts→
1 cd/m² = 0.29186 fL
Foot-lamberts to cd/m²→
1 fL = 3.42626 cd/m²
1,000 Nits (HDR) to fL→
1,000 Nits ≈ 291.86 fL
14 fL (Cinema Standard) to Nits→
14 fL ≈ 48 Nits

Luminance Reference Equivalents (1 Candela per square meter)

Standard ratios measured against the base Candela per square meter (cd/m²)

Reference Table
Unit NameSymbolEquivalent in 1 cd/m²Quick Pair Page
Candela per square metercd/m²1 cd/m² = 1 cd/m²Base Unit
Nitnit1 cd/m² = 1 nitcd/m² to nit →
Foot-lambertfL1 cd/m² = 0.291864 fLcd/m² to fL →

Display Screen & Natural Surface Luminance Reference Chart

Lookup table of surface luminance values from dark movie theaters to high-end OLED smartphones and outdoor billboard displays

Lookup Matrix
Display / Physical SurfaceNits (nit)cd/m² (SI Standard)Foot-lamberts (fL)Display Industry Standard Tier
Standard Commercial Movie Cinema Screen48.0 nit48.0 cd/m²14.0 fLDCI Cinema Specification (SMPTE)
Standard Laptop LCD Screen (Indoor Work)250.0 nit250.0 cd/m²72.96 fLBasic Office SDR Display
High-End Desktop IPS Creative Monitor400.0 nit400.0 cd/m²116.74 fLVESA DisplayHDR 400
Mid-Tier HDR Television (Mini-LED / QLED)600.0 nit600.0 cd/m²175.12 fLVESA DisplayHDR 600
Premium OLED TV Peak Highlight Window1,000.0 nit1,000.0 cd/m²291.86 fLMastering Studio Reference HDR
Smartphone Screen (Typical Indoor Max)800.0 nit800.0 cd/m²233.49 fLModern OLED Mobile Typical
iPhone 15 / Galaxy S24 Outdoor Peak Sun2,000.0 nit2,000.0 cd/m²583.72 fLHigh-Brightness Outdoor Mode
Commercial Outdoor Digital LED Billboard5,000.0 nit5,000.0 cd/m²1,459.3 fLDirect Sunlight Sunlight Readable
Fluorescent Light Tube Surface10,000.0 nit10,000.0 cd/m²2,918.6 fLDirect Light Source Surface
Direct Disk of the Sun at Noon1,600,000,000 nit1.6 × 10⁹ cd/m²4.67 × 10⁸ fLSolar Disk Radiation
Photometry & Display Engineering

Luminance: Screen Brightness, Nits, HDR Standards & Visual Optics

Authoritative guide to surface luminance, candela per square meter, HDR10 mastering specifications, and unit conversions across display monitors and projection systems.

Physical Definition of Surface Luminance

Luminance characterizes the visual sensation of surface brightness perceived by a human eye observing an illuminated or light-emitting object:

L = dI / (dA · cos(θ)) = d²Φ / (dA · cos(θ) · dΩ)

Luminance Formulation (I = Luminous Intensity in Candelas, A = Surface Area in m², θ = Viewing Angle relative to surface normal)

In Lambertian diffuse surfaces (such as matte paper or chalk), luminance is independent of the viewing angle: the surface appears equally bright from any perspective because the projected area dA · cos(θ) decreases at exactly the same rate as the directional intensity.

Nits vs cd/m² vs Foot-Lamberts in Display Tech

Display engineers utilize specific standards across consumer and theatrical sectors:

Consumer Electronics: Nits (cd/m²)

1 Nit = 1 cd/m². Used across specifications for TVs, laptops, tablets, and smartphones. VESA DisplayHDR specifications classify performance into HDR400, HDR600, HDR1000, and HDR1400 based on peak sustainable nits.

Theatrical Cinema: Foot-Lambert (fL)

1 fL = 1/π cd/ft² ≈ 3.426 cd/m². Retained by the Society of Motion Picture and Television Engineers (SMPTE) and DCI cinema standards: standard 2D cinema requires 14 ± 3 fL, while 3D cinema allows 3.5 to 7 fL.

High Dynamic Range (HDR) & Electro-Optical Transfer Functions

Legacy standard dynamic range (SDR) video was mastered to a peak luminance of 100 Nits using gamma curves. Modern HDR formats (HDR10, Dolby Vision) utilize the Perceptual Quantizer (PQ / SMPTE ST 2084) transfer function, capable of encoding absolute luminance levels from 0.0001 Nits up to 10,000 Nits to recreate real-world specular highlights (glints on chrome, fire, explosions, and sunlight reflections).

About Luminance Units & Formulas

1 Nit = 1 cd/m² | 1 Foot-lambert ≈ 3.426259 cd/m².

Candela per square metercd/m²

SI unit of luminance

Nitnit

Screen display brightness unit (1 cd/m²)

Foot-lambertfL

Cinema projection brightness unit

FREQUENTLY ASKED QUESTIONS

Luminance Converter FAQs

Frequently asked questions regarding luminance conversion metrics, formulas, and real-world calculation standards

Is 1 Nit exactly equal to 1 cd/m²?

Yes, 1 Nit is exactly identical to 1 Candela per square meter (1 nit = 1 cd/m²).

"Nit" originates from the Latin word nitere (to shine) and is the popular terminology used by consumer electronics manufacturers (Apple, Samsung, LG, Sony) to describe monitor and television screen brightness. "Candela per square meter" is the formal SI derived scientific unit.

How do you convert Nits (cd/m²) to Foot-lamberts (fL)?

To convert Nits to Foot-lamberts (fL), divide by 3.426259 or multiply by 0.291864: fL = Nits × 0.291864.

Cinema Example:

  • Digital cinema projection standards (DCI / SMPTE 196M) require a theatrical screen brightness of 14 Foot-lamberts: 14 × 3.4263 = 48 Nits (cd/m²).
  • Reverse Conversion: Multiply Foot-lamberts by 3.426259 to get Nits (e.g., 100 fL × 3.4263 = 342.6 Nits).

What is luminance in physics?

Luminance (L_v) is a photometric measure of the luminous intensity per unit area of light traveling in a given direction. It describes the amount of light that passes through, is emitted from, or is reflected by a particular area, and falls within a given solid angle:

L_v = d²Φ / (dA · cos(θ) · dΩ)
  • SI Unit: Candela per square meter (cd/m²).
  • Human Perception: Luminance is the objective physical counterpart to the subjective perception of brightness. An eye or camera sensor perceives an object as bright or dim based strictly on its luminance.

How many Nits do you need for comfortable outdoor smartphone visibility?

For clear legibility under direct midday sunlight, a smartphone screen requires a minimum brightness of 1,000 to 1,500 Nits.

Standard indoor displays (250–400 Nits) appear washed out and unreadable outdoors because reflected ambient daylight overwhelms the screen's emitted luminance. Modern flagship smartphones feature specialized "High Brightness Modes" (HBM) capable of boosting peak window brightness to 2,000 to 2,600 Nits.