Lumens vs Nits : What’s the Difference?

Comparing two units of brightness can be confusing when they are measured in differing units. Here we look at a common comparison of lumens vs nits, required to correlate between different sources of a screen or display, to understand the difference and relationship between the two.

What is a Lumen?

A lumen quantifies the amount of visible light emitted from a given light source.

The ANSI Lumen rating is the most common measure of brightness used by projectors, and it’s generally considered to be the most accurate method to compare different projector models.

Why Are Lumens Important?

Lumens are a unit of measurement that directly affect the brightness of your projector or screen. The brighter you need your image to be, the higher its lumen rating should be.

What is a Nit?

The nit is a unit of measurement that quantifies the luminance of an object or how much visible light an object emits and is being seen.

1 nit is equal to 1 candela per square meter (cd/m2).

1 NIT = 1 cd/m²

The unit of a NIT is derived from the latin word ‘nitere‘, meaning ‘to shine’.

Why Are Nits Important?

The brightness of a digital display or screen and how it appears to the human eye are often quantified in nits.

Nits are important because they directly affect the perceived brightness of a screen. The higher the nit rating, the brighter your screen will appear.

What is the Difference Between Lumens vs Nits

Lumens or ANSI lumens are used as a measurement of how much light is being projected whereas the Nit unit defines the luminance or brightness of an object.

Both are used to quantify optical output but Lumens are a unit of light created, whereas Nits are a unit of measurement for how much visible light is being seen.

In terms of displays, lumens measure a projector’s output and nits measure the screen’s brightness.

Lumens to Nits Conversion

Although Nits and lumens are two different units of measurement, there is a way to convert between the two to assist in a comparison between different sources, such as comparing the brightness of a projector with a TV or display screen.

The ratio for the difference between Nits and Lumens is:

• 1 Nit = 3.426 Lumens
• 1 Lumen = 0.29 Nits

Therefore, 1 Nit is perceived as brighter than 1 Lumen.

Lumens vs Nits Conversion Table

Comparing Brightness

Comparing lumens to nits is ultimately a brightness comparison so you can understand which value will be visibly brighter.

For example, when comparing the brightness of a projector to a TV or display:

• 400 nits brightness of a screen is equivalent to 1370 lumens from a projector
• 2000 lumens of projected light = 613 nits of screen luminance

So in terms of choosing displays, TVs and projectors, the difference between light output and ‘brightness’ or the luminance of a screen, can be calculated and compared.

However, you must remember that perceived brightness is not entirely defined by a value but dependent on other determining factors, such as the size of a projected screen and its distance from the source, the viewing conditions, ambient lighting levels, and most importantly contrast.

Brightness is a subjective measurement of how bright or dark something appears, and although we use it as a description of luminance, ‘brightness’ does not produce luminance, merely how we perceive it.

So when trying to compare the brightness of two light sources, you must consider all relevant factors to ensure an accurate comparison.

The comparison of ANSI Lumens vs Lumens will also help you make better informed brightness decisions.

Andrew Orange, the owner of Orange Lighting qualified and worked as an interior designer in 1993 before specialising in lighting working on high profile projects based in London. Since starting Orange Lighting Ltd in 2003 he has been sharing his knowledge and unique teaching style mostly to his designer clients, offering practical real life advice born from running a busy consultancy and lighting supply business. Launching in 2020, his blog has evolved into Quick & Easy Lighting, curating some 25 years design experience into making the lighting choice and design process achievable and easy to understand for all.