How to Tell What Percent Tint You Have? (with Calculate Example)

Many drivers think about having their windows tinted, but only a few know everything about the tint percentage allowed. Once you apply the film to the glass, you probably ask yourself how to tell what percent tint you have. It is a crucial question, particularly if you plan to travel to another state.

As you know, each US state has its own law about that subject so that you can be fined because of the wrong window tinting percentage. Some levels are strictly forbidden because they are a barrier to clear vision and can cause an accident. Let’s talk about the subject.

Window Tint Percentage Types

Most drivers decide to have their car windows tinted because of a few reasons, such as:

  • The film enhances the car’s aesthetics
  • Tinting increases privacy
  • Applied film lowers the temperature inside the car
  • Tint blocks harmful UV rays
  • The high-quality film prevents glare

In theory, you can choose window tint options from 5% to 90%, referring to the visible light transmission amount coming through the window. The tint you pick out for your vehicle will be darker with a lower percentage.

No tint – In this case, you have regular factory windows without tinted glass. They provide excellent visibility but create glares while driving and can’t block UV rays or reduce heat.

50% tint – It is an excellent option for drivers who want to avoid complete darkness since this film blocks only half the light coming inside the car. This percentage is still enough to reduce glare and block heat and UV rays while making driving safe.

35% tint – Most drivers enjoy this option since cars with such darkened windows look fantastic and classy. On the other hand, this percentage still allows a clear view through the windows.

20% tint – Such a low percentage provides enough privacy, but it is at the limit of clear visibility.

5% tint – This highly dark film is forbidden for vehicles in all US states and most countries worldwide. However, it is possible applying it to the limousines’ back windows.

The US

Be careful with tinting since too low percentages are illegal in most states. If you have installed such a film, you can count on fines when the police stop you. Plus, you will be forced to remove existing tinting and replace it with the one according to the law.

Allowed tint window percentage by state

State Window (car / multi-purpose vehicle)
Rear Back side Front side
Alabama 32% / No limit 32% / No limit 32%
Alaska 40% / No limit 40% / No limit 70% / No limit
Arizona No limit No limit 33%
Arkansas 10% 25% / 10% 25%
California No limit No limit 70%
Colorado 27% 27% 27%
Connecticut No limit 35% / No limit 35%
Delaware No limit No limit 70%
Florida 15% 15% 28%
Georgia 32% / No limit 32% / No limit 32%
Hawaii 35% / No limit 35% / No limit 35%
Idaho 35% / No limit 20% / No limit 35%
Illinois 35% / No limit 35% / No limit 35%
Indiana 30% / No limit 30% / No limit 30%
Iowa No limit No limit 70%
Kansas 35% 35% 35%
Kentucky 18% / No limit, 8 inches (20.5 cm) from the top 18% / No limit, 8 inches (20.5 cm) from the top 35%
Louisiana 12% / No limit 25% / No limit 40%
Maine 35% / No limit 35% / No limit 35%
Maryland 35% / No limit 35% / No limit 35%
Massachusetts 35% 35% 35%
Michigan No limit No limit No limit, 4 inches (10 cm) from the top
Minnesota 50% / No limit 50% / No limit 50%
Mississippi 28% / No limit 28% / No limit 28%
Missouri No limit No limit 35%
Montana 14% / No limit 14% / No limit 24%
Nebraska 20% / 35% 20% / 35% 35%
Nevada No limit No limit 35%
New Hampshire 35% / No limit 35% / No limit Not allowed
New Jersey No limit No limit Not allowed
New Mexico 20% / No limit 20% / No limit 20%
New York No limit 70% / No limit 70%
North Carolina 35% / No limit 35% / No limit 35%
North Dakota No limit No limit 50%
Ohio No limit No limit 50%
Oklahoma 25% / No limit 25% / No limit 25%
Oregon 35% / No limit 35% / No limit 35%
Pennsylvania 70% / No limit 70% / No limit 70%
Rhode Island 70% / No limit 70% / No limit 70%
South Carolina 27% / No limit 27% / No limit 27%
South Dakota 20% / No limit 20% / No limit 35%
Tennessee 35% 35% 35%
Texas No limit  No limit 25%
Utah No limit No limit 43%
Vermont No limit No limit Not allowed
Virginia 35% / No limit 35% / No limit 50%
Washington 24% / No limit 24% / No limit 24%
Washington DC 50% / 35% 50% / 35% 70%
West Virginia 35% / No limit 35% / No limit 35%
Wisconsin 35% 35% 50%
Wyoming 28% / No limit 28% / No limit 28%

As you can see, US states have different laws and traffic regulations regarding car window tinting. Whatever laws are, they are crucial for preventing possible car accidents and putting yourself and other road users at risk.

The UK

By the Britain law, windows must let 70 to 75% of sunlight through. Since most vehicles come with window glass featuring up to 70% VLT, applying even a light tint over the original glass will be illegal.


It is allowed to have side windows tinted up to 35% VLT in Australia but without reflective tints. On the other hand, the windscreen film is limited to 70 to 75% VLT.



You should be aware that sunlight hits the glass and then can:

  • Pass through glass (transmittance level)
  • Bounce off the glass (reflection level)

According to this, you can recognize two crucial values:

Visible light reflection (VLR) – It shows you the percentage of solar energy reflected off the car window.

Visible light transmission (VLT) – It shows the sunlight amount that penetrates through the window tint.

Unlike darkened windows, transparent glass won’t absorb much visible light, and the absorption level directly depends on the tinting percentage. If you have tinted your windows with a film featuring a high VLR, it will block most of the light and prevent it from passing through the glass.


Factory Tint vs. Applied Tint

Factory tint is a car’s window darkening level installed during production. A new trend is to get a vehicle with darker windows, and you can often find models with originally tinted rear windows.

In most cases, this glass tint percentage on rare windows is 15% to 20%, which blocks 80 to 85% of visible light and lets approximately 15 to 20% inside the vehicle. On the other hand, the original tint for side windows is 70 to 80%.

In some states, it is allowed to increase the window darkness by applying an aftermarket film over the original one. In that case, you should calculate the additional darkness level to prevent violating state traffic rules.


Ways to Calculate Window Tint Percentage

It is uncomplicated to pick out the proper film for your car if it came without window tint installed. In that case, you don’t need to calculate the tinting percentage because it will be equal to the value of the film itself.

For instance, a tint with 70% VLT will block 30% of the sunlight while the rest of 70% passes through the glass. The darker the film you apply, it will reflect more light off the windows, and less light will get through them and enter inside the car.

The problem appears with vehicles featuring factory-tinted windows. In that case, you need to calculate how much light comes through the windows before applying the film to prevent exceeding the legal limit in your state. To get that value, you should multiply the VLT value of the film and the VLT of the original glass:

Film VLT x original glass VLT = final tint percentage

Lat’s take an example:

  • The film VLT is 6%
  • The factory VLT is 70%

The final tint percentage after the film installation would be:

  • 5% x 70% / 100% = 3.5% VLT tint

Another option is to apply a film with VLT 50% to a glass with an original 70% tint. In that case, the result will be:

  • 50% x 70% / 100% = 35% VLT tint

As you can see, VLT will be significantly lower after combining applied film and an already existing window tint.



If you have tinted windows on your vehicle, you should know how to tell what percent tint you have. It is crucial since too low percentages are forbidden in most states. Moreover, you can pay a ticket if you have the wrong tinting percentage levels on each window. Be on track and do your best to prevent possible accidents!

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