Tint Percentage Calculator (VLT + Layering)

Calculate window tint percentage from film and original glass VLT, or estimate net VLT and legal status by state and window position.

Solve for

Factory glass VLT (%)

The light let in by the bare factory glass before any film. Untinted auto glass is usually 70 to 88 percent; privacy glass in rear windows can be far lower.

Tint film VLT (%)

The VLT rating printed on the film, such as 35 or 5. Lower means darker.

Add a second film layer

Second film VLT (%)

Only if you are stacking a second film on top of the first.

Target final VLT (%)

The final darkness you want to end up with after the film is on, for example 35 to match a common legal limit.

More options

Tint percentage is VLT, the share of visible light let through. Layers multiply, so a film on tinted glass is always darker than either one alone. Check the final VLT against your local limit before buying film.

Related Calculators

VLT Level Reference

Higher VLT = more light through. Most states set front-side window minimums between 24% and 70% VLT. Rear windows in many states have no restriction.

Net VLT	Appearance	Typical Legal Status (Front Windows)	Privacy Level
70%	Nearly clear	Legal in all states	None
50%	Light tint	Legal in most states	Low
35%	Medium tint	Legal in many states; illegal in CA, NY, PA front	Moderate
20%	Dark tint	Rear windows only in most states	High
5%	Limo tint	Rear only in select states; illegal on front everywhere	Maximum

Tint Percentage Formula

TP = VLTt / 100 * VLTg / 100 * 100

TP = Net Tint Percentage (%)
VLTt = VLT of the window tint film (%)
VLTg = VLT of the original glass (%)

Typical Factory Glass VLT by Window Position

The original glass VLT is the value to enter as the starting point. Most front glass is clear-grade (70%+) while most factory privacy glass on SUVs, trucks, and minivans sits at 15 to 26%. If you apply a 35% film to a rear window already at 20% factory glass, your net VLT drops to 7%, which is illegal nearly everywhere for rear side windows with minimum requirements.

Window Position	Typical OEM VLT Range	Notes
Windshield	74 to 85%	UV-blocking laminated glass; many include a blue or green tint band across the top
Front side windows	70 to 74%	Tempered glass; most states require 70%+ net VLT after film
Rear side windows (privacy glass)	15 to 26%	Standard on most SUVs, crossovers, and trucks; this is baked-in pigment, not a film
Rear windshield	70 to 85% (clear) or 15 to 26% (privacy)	Sedans typically clear; SUVs and trucks often privacy glass depending on trim

Film Technology and Heat Rejection

VLT only measures visible light. Heat (infrared radiation) is a separate spectrum, meaning two films at the same VLT can differ dramatically in heat rejection depending on film technology. A ceramic 35% film blocks up to 95% of infrared versus roughly 0% for a dyed 35% film.

Film Type	IR (Heat) Blocking	UV Blocking	Signal Interference	Durability
Dyed	Low; absorbs heat and re-radiates into cabin	~99%	None	Fades; can turn purple over time
Metalized	Moderate; reflects infrared	~99%	Blocks GPS, cell, and radio signals	Good
Carbon	~40% IR blocked	~99%	None	Good; matte finish resists fading
Ceramic	Up to 95% IR blocked	~99.9%	None	Best; no color shift or signal loss