Florida measures tint by visible light transmission, or VLT: the percentage of light that passes through the glass and film together. A lower number means a darker window. The legal limit is different for each window, and it changes depending on whether you drive a sedan or a multipurpose vehicle like an SUV, truck, or van.
Front side windows are the same for everyone: they must let in more than 28% of light. This is the window an officer looks through during a traffic stop, so it's the one Florida is strictest about.
Rear side windows and the back glass are where the vehicle type matters. On sedans and coupes, they must let in more than 15% of light. On SUVs, trucks, and vans, they can go as dark as 6%, which is why so many SUVs come from the factory with dark privacy glass in back.
The windshield can only be tinted above the manufacturer's AS-1 line, a small marking near the top of the glass. That's where a sun strip goes. Florida also limits how reflective tint can be, which rules out most mirror-like films on the side windows.
Drivers with certain medical conditions can apply to the state for an exemption that allows darker tint. If that's you, sort out the exemption before the install. Either way, we explain the limits for your exact vehicle before any film goes on, so you end up with a look you like and no reason to get pulled over.