What the number means
VLT is the share of visible light that passes through the glass and film together. A thirty five percent film lets roughly a third of the light through. Lower numbers are darker.
Two things it does not measure. It says nothing about infrared heat, which is what makes a car hot; and it says nothing about ultraviolet, which is what fades an interior. Films publish those separately, and the gap between them is where most of the money in a tint quote goes.
The definition on its own is vlt meaning, and the longer explanation of how shops talk customers through it is what is vlt tint.
Darker is not cooler
This is the single most useful thing on this page. One manufacturer's published spec sheet for its ceramic line shows total solar energy rejection of 71 percent at its darkest shade and 52 percent at its lightest: a real difference, but far smaller than the visual difference between those two films.
Compare that with a basic dyed film, which is dark and rejects very little heat, and the point lands: within a film line, going darker buys you a little more heat rejection. Between film lines, going from dyed to ceramic buys you a lot, at the same shade.
So if the complaint is heat, the money belongs in the film, not in the darkness. If the complaint is privacy or looks, the darkness is exactly what you are buying and a cheaper line may be fine.
| Shade | Total solar energy rejected | UV rejection |
|---|---|---|
| Darkest (5) | 71% | 99% |
| 15 | 69% | 99% |
| 20 | 66% | 99% |
| 35 | 59% | 99% |
| Lightest (70) | 52% | 99% |
From one manufacturer's public specification sheet for one ceramic line, measured to the EN 410 method. Other lines and brands publish different figures; ask for the spec sheet for the exact film you are quoted.
What each shade is like to live with
Owners comparing shades on car forums are remarkably consistent, and their descriptions are more useful than any chart.
- Fifty percent and lighter: barely reads as tint. Bought for heat and UV rather than looks, and invisible to most people.
- Thirty five percent: the common answer. Private enough in daylight that people do not look in, and close enough to normal at night that reversing in the rain is unchanged.
- Twenty percent: clearly dark, and a real adjustment after dark. Owners repeatedly describe twenty as fine in daylight and awkward at dusk and in rain.
- Five percent, sometimes called limo: for rear glass on some vehicles. At night, through a rear window, it is close to opaque.
- A common split is a lighter shade on the front doors and darker behind, which is also how many legal frameworks are structured.
The legal part, honestly
How dark you may go is law where you live. Limits differ between front side windows, rear side windows, the rear windshield and the windshield strip; they differ by state and province; and they change.
This page deliberately does not print a table of them. A stale legal table on a consumer page is worse than no table, and getting it right needs statute-level sourcing rather than a summary of somebody else's summary.
So: ask the shop what they fit locally, and check your own state or province regulator yourself before you settle on a number. A shop that volunteers the local limits without being asked is a good sign.
The rest of the booking conversation is on questions to ask a tint shop, and published prices by film type are on window tint cost.
How to actually choose
Three questions, in this order. What is the problem: heat, glare, privacy or looks? If it is heat, buy the film line first. Then: how much night driving do you do, and in what weather? That sets the floor on shade. Then: what does the law where you live allow on each window?
Ask the shop to hold sample cards against your own glass, in daylight, outside. Tint looks completely different on a card in a showroom and on a car in a car park, and fifteen minutes there saves a removal bill later, published at tint removal cost.
Sources & notes
Facts checked
- 1.Visible light transmission and total solar energy rejected by shade, UV rejection and the EN 410 measurement method: manufacturer public specification sheet for one ceramic window film line, read 22 September 2026. xpel.com
- 2.Owner descriptions of 20 versus 35 percent for night driving and rain: car enthusiast forum threads, read 22 September 2026. Quoted as what owners report, not as measurement. bobistheoilguy.com
- 3.Film type price differences referenced when comparing dyed and ceramic: published 28 January 2026, read 22 September 2026. goodcar.com
Legal darkness limits are not stated anywhere on this page and nothing here is legal advice. Specification figures are one manufacturer's, for one film line, on one date.
Questions people ask
What tint percentage should I get?
Thirty five percent is the shade most daily drivers settle on: private in daylight, close to normal at night. Choose the film line first if heat is your problem, then pick the darkest shade your local law allows and you are comfortable driving at night.
Does darker tint keep the car cooler?
Only slightly, within one film line. One manufacturer's published figures show total solar energy rejection going from 71 percent at its darkest to 52 percent at its lightest. Moving from a dyed film to a ceramic film changes heat far more than moving a shade darker.
Is 20 percent too dark for night driving?
It is a real adjustment. Owners comparing 20 and 35 percent consistently report that 35 feels close to normal after dark while 20 takes getting used to, particularly in rain and when reversing.
What is the legal tint limit?
It depends entirely on where you live, and it differs per window. This page does not print a table because those limits change and a stale one is worse than none. Ask your installer and check your own state or province regulator.