What is VLT? How dark are your lenses?

A private pilot wearing glasses and holding clip-on sunglasses in the cockpit

Dark sunglasses protect your eyes from the sun and prevent strain, but how can you find the right tint? We’re here to shine some light on VLTs and what a VLT percentage means for your eyewear experience.

Visible Light Transmission (VLT) refers to the amount of light that passes through your lens.

Lenses with a higher VLT percentage will be brighter while a lower VLT percentage will be darker. To help determine which percentage you should be looking for, VLTs are categorized in 5 ranges based on their performance in varying light conditions.

A motorcyclist wearing white sunglasses looking out at a sunset

Category 0) 80-100% - Virtually zero tint, great for when the sun is out of the picture.

Category 1) 43-80% - Light tinting, a possible option for overcast days.

Category 2) 18-43% - Medium tinting, perfect for low-light conditions.

Category 3) 8-18% - Dark lenses, the go-to for sunny days.

Category 4) 3-8% - Very dark lenses, only for extremely bright conditions.

For outdoor regulars, we recommend lenses in Category 3 to block the sun while maintaining optimal visibility down the road or through the skies. Also consider the tint color: 

An ADV motorcycle rider putting on sunglasses.

 - Gray tinting reduces brightness without distorting colors.

 - Rosy tinting enhances contrast.

 - Mirrored lenses utilize reflective coatings to reduce glare.


Pilots must maintain clear visibility of the instrument panel at all times, which is where gradient tints can be helpful. These tints offer a dark tint at the top of the frame with a reduced tint further down the lens. Switch between VLTs with one pair of shades by using clip-on shades or go with photochromic lenses designed to transition from lighter to darker VLTs depending on the light.

A private pilot overlooking the New York skyline while flying in his Grumman

Understanding Visible Light Transmission (VLT)  is essential for selecting sunglasses tailored to the specific needs of any adventure enthusiasts. Whether soaring through the skies, cruising on a motorcycle, or embracing the great outdoors, the right VLT ensures optimal vision and eye protection. Consider the lighting conditions of your activity and choose sunglasses with the appropriate VLT and lens tint to enhance your visual experience and eye safety.