What is the darkest tint?

The darkest window tint available is typically 1 percent to 5 percent visible light transmission, with 5 percent commonly called limo tint being the darkest widely available from major manufacturers, and some specialty films offering 1 percent or even 0.5 percent. Tint darkness is measured by VLT, visible light transmission, which is the percentage of light that passes through. A lower VLT means darker tint. 5 percent tint allows only 5 percent of light through, blocking 95 percent, making it very difficult to see inside during the day and very dark from inside at night. Some companies make 3 percent, 2 percent, or 1 percent films that are even darker, blocking 97 to 99 percent of light. In practice, 5 percent is considered the darkest practical tint because anything darker than that makes night driving extremely dangerous due to severely reduced visibility. For windshields, the darkest legal is usually 70 percent or higher, which is almost clear. For front side windows, most states require 25 to 70 percent. The absolute darkest physically possible would be 0 percent, which would be fully opaque like black paint, but that is not sold as window tint because you could not see out at all. So the darkest commonly sold and used is 5 percent limo tint.