Tinted Lens Categories

Below is a quick breakdown of the different VLT (visible light transmittance) categories:

Category 0: Blocks 0 to 20% of light; sunglasses in this category are typically more style-forward glasses that allow almost all, if not all, light through.

Category 1: Blocks 20 to 57% of light; these shades have a slight lens tint and are okay for wear when the sunlight is of very low intensity.

Category 2: Blocks 57 to 82% of light; available with darker lens tints, a category 2 shade can be worn in average light.

Category 3: Blocks 82 to 92% of light; these sunglasses have very good light-blocking abilities and do a great job blocking intense sunlight and even glare.

Category 4: Blocks 92 to 97% of light, if you’re looking for the most light-blocking sunglasses, lenses in this range allow the least amount of light through.

The best sunglasses for light-sensitive eyes will offer either a Category 3 or Category 4 lens. A Category 3 lens is the darkest pair you can get that will let you safely drive — but if you’re not hopping behind the wheel, a category 4 lens blocks the most visible light and may be more comfortable for you.

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