Lens categories simply explained

Hannah Neuhauser
04.07.2025

Sporty cycling glasses with a “shield” look have long been an integral part of countless sports. They have also become a must-have in the lifestyle and fashion sector. However, in addition to the visual factor, the function of the sports glasses is of course crucial. Wearing comfort, optimum ventilation and, of course, good vision are decisive factors. In this blog, we explain everything about the last point, optimal vision and how to choose your sports or fashion glasses so that you have the best view.

Lens tinting and categories

If you have ever bought a pair of cycling glasses, you will certainly have heard the term “lens tint” before. This defines the color of the lenses and also how strongly or weakly the glasses darken surrounding light. So that you know exactly which tint is right for you, different categories are given for the lenses of sports glasses.

Sports glasses VLT value

But how exactly do these lens categories come about? This depends on the so-called VLT index (Visible Light Transmission Index). This describes how much visible light can shine through a lens and is not blocked. A VLT value of 100% means that 100% of all visible light rays pass through the lens. The lower the VLT value, the darker the lens and the more visible light is blocked. To make this easier when buying, sports lenses are divided into corresponding categories. The following table provides a simple overview of the areas of application of the lenses:

Light transmission (VLT)

Category (CAT.)

Conditions

Suitable for

100-81%

CAT. 0

Very low light

Night and very bad weather

80-44%

CAT. 1

Little light and poor conditions

Rain and shady forest

43-19%

CAT.2

Changeable to normal conditions

Cloudy and partly sunny weather

19-9%

CAT. 3

Normal to fair conditions

Bright daylight

8-3%

CAT. 4

Very nice conditions

Bright sunshine / glacier

 

Different VLT - sports glasses with interchangeable lenses


Different lens categories ensure that you have the right sports glasses for any weather. So that you don't have to buy 5 different pairs of glasses, cycling glasses with interchangeable lenses or photochromic sports glasses are available. Here you can read about the big difference between interchangeable lenses and self-tinting sports glasses.

Credits: Elias Neier

 

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