What Are the Categories of Sunglasses?
Ultraviolet (UV) protection is crucial for your eye health and vision during every season of the year, on sunny days and cloudy ones too. Unprotected UV exposure has been linked to several eye conditions, including cataracts, macular degeneration, and pterygium (surfer’s eye).
Wearing sunglasses with 100% UVA-UVB lens protection helps to block the sun’s harmful UV rays and prevent eye damage and disease from occurring. Getting the proper UV protection is important, but it’s not the only thing to consider when shopping for sunglasses.
Lens tint (colour and level of darkness) is another factor to keep in mind when choosing your next pair of shades. In the UK, sun lenses are divided into five sunglasses categories based on how much light passes through the lenses.
Read on for a review of sunglasses categories, why they matter, and how you can tell if the shades you want will have the UV protection your eyes need.
Overview of Categories
In the UK, there are five categories for eyeglass and sunglass lenses based on their percentage of visible light transmission (VLT). This system is used to describe the amount of light that passes through lenses, in categories 0 through 4.
Each numbered sunglasses category indicates the level of lens tint, from clear to very dark lenses. Clear lenses and those tinted with lighter colours have a higher VLT percentage because more light passes through to your eyes. Since they filter less light, they have a lower category number.
Darker lenses have a lower VLT percentage because they allow less light through to your eyes. This means they filter more light, so they have a higher category number.
It’s important to note that sunglasses categories and VLT percentages are used to indicate how much light can pass through the lenses to your eyes. Sunglass categories and VLT percentages do not refer to or affect the level of UV protection the lenses provide.
5 Category Types
Which sunglasses category is right for your lenses? It depends on the activities you participate in and how much shade you like for your eyes. You can get lenses with a very light tint or lenses with a very dark tint, or a tint in between. Some are better suited for daily wear, and some should be reserved for the brightest circumstances.
Remember that no matter how light or dark the lenses are, you should still look for sunglasses that provide 100% UVA-UVB lens protection.
Here is a review of the five sunglasses categories and the situations they may be best for:
Category 0 Sunglasses
Category 0 lenses are best suited for safety glasses and corrective eyewear made to improve your vision. These lenses are either clear or have a pale tint.
- Lens tint: Clear or ultra-light tint
- VLT: 80% to 100%
- Ideal for: Eyeglasses and safety glasses
Category 1 Sunglasses
Lenses in Category 1 are lightly tinted, with either a light or yellowish hue. These lenses are perfect as fashion accessories, but they’re less fit for bright environments.
- Lens tint: Yellow or another light tint
- VLT: 43% to 80%
- Ideal for: Fashionable eyewear
Category 2 Sunglasses
Category 2 lenses are darker than Categories 0 and 1, but they may not be suitable for overly bright days. They’re better for moderately sunny settings.
- Lens tint: Blue, orange, rose, red, or another medium tint
- VLT: 18% to 43%
- Ideal for: Overcast days or environments with limited brightness
Category 3 Sunglasses
Category 3 sunglasses are designed for daily wear. They offer quality shade whether you’re strolling through the park or enjoying a day of outdoor sightseeing.
- Lens tint: Green, grey, brown, or another dark tint
- VLT: 8% to 18%
- Ideal for: Everyday wear
Category 4 Sunglasses
The darkest of the sunglasses categories is Category 4. These are best for supremely bright environments, such as those you might find on a trekking tour or ski trip. You should never wear Category 4 sunglasses while driving.
- Lens tint: Dark brown, dark grey, or another very dark tint
- VLT: 3% to 8%
- Ideal for: Extremely bright settings (not for driving or everyday use)
While darker tints may provide shade and relief on sunny days, they aren’t guaranteed to provide UV protection unless they are labelled accordingly.
Does Category 3 Mean Polarised Lenses?
No. Lens categories, including Category 3, are assigned based on the level of visible light that is transmitted through the lenses. Polarised lenses have a special filter that reduces glare from reflective surfaces like water, roadways, and snow and helps you see more comfortably and clearly in those conditions.
Polarised sunglasses come in a variety of lens colours, and most often fall into Category 2 or Category 3.
How to Tell If a Pair of Sunglasses Offers UV Protection
Just because your sunglasses have dark lenses, it doesn’t mean they automatically block the sun’s harmful ultraviolet rays. To ensure your shades provide proper protection, look for a label that states 100% UVA-UVB lens protection or UV 400. UV400 means that the lenses provide 100% UVA-UVB lens protection.
When you shop for eyewear online, the product description should indicate whether the lenses include UV protection. When buying a pair of shades in person, ensure they are labelled 100% UVA-UVB lens protection or UV 400.
If you have a pair of sunglasses but aren’t sure if they have the right protection, you can get them tested at an optical store. Many opticians will test your lenses for free.
Talk to your eye care professional if you have any questions or concerns as you shop for sunglasses. And make sure to attend routine eye tests to maintain your eye health and vision care! Eye tests are the best way to detect serious conditions early, including those that may occur due to increased sun exposure.
Sources
- Protecting your eyes from the sun’s UV light. National Eye Institute. July 2022.
- Sunglasses categories and UV protection. Glasses Direct. Accessed June 2024.*
- Polarised lenses. Glasses Direct. Accessed June 2024.*
- What’s the best UV protection for sunglasses? All About Vision. March 2020.*
- Are eye exams just as important as other health exams? All About Vision. April 2022.*
The sources listed here have been provided for informational purposes only. The citation of a particular source does not constitute an endorsement or approval of EssilorLuxottica products, services, or opinions by such source.
*Like Foster Grant, All About Vision, Glasses Direct, and AAV Media, LLC are affiliates of EssilorLuxottica.