Window Tint Percentages

In the window tinting industry and the laws that surround it, window tint on a vehicle is usually measured by a percentage number. Most often, this is rated by its Visual Light Transmission (VLT) percentage. This is a measurement of the amount of visual light that the window allows through.

A note on window tinting: every state has laws on window tint allowances. Be sure to know yours before tinting your vehicle's windows!

How the VLT Works

The VLT number on a window refers to the amount of visible light that is allowed through from the outside in. The smaller the VLT number, the less light that is allowed through. A "limousine tint," for instance, has a VLT of about 5%. This means only 5% of the light in the bright of day gets through the windows to the interior.

Most vehicles have a built-in tint from the factory of about 90%. Eliminating just 10% of the sun's light can mean huge savings in energy requirements to cool the car. This results in an increase in cabin comfort and makes the tint worth the tiny expense to the manufacturer.

Note: if tinting your own windows, be aware of this factory tint as it will add to whatever tint you're installing, potentially making the overall VLT illegal.

For the most part, when car owners take their vehicles in for tinting, they are usually asking for a 30-35% VLT on the finished product. In most areas of the country, this is legal except on the windshield, which is required by federal law to be tint-free (with the exception of darkening strips along the top).

Understanding what the percentages mean when you talk to a technician about tinting your windows will go a long way towards knowing what it is that you're getting.