That “put a glass of salt in your car” claim is another viral life-hack exaggeration. It mixes a small amount of truth with a lot of overstatement.
What salt actually can do
Salt is hygroscopic, meaning it can absorb a small amount of moisture from the air. So in theory:
- It may slightly reduce humidity in a very small, enclosed space
- It can help a bit with minor dampness or fogging
Why it’s NOT a real car solution
In a car, this hack is basically ineffective because:
- Car interiors are not airtight, so humidity keeps coming back
- A glass of salt absorbs very little moisture compared to a real dehumidifier
- It can spill and damage interior surfaces (salt is corrosive over time)
- It does nothing for condensation on windows in real driving conditions
What actually works better 🚗
If your goal is foggy windows or moisture control:
- Use proper car dehumidifier packs (silica gel or calcium chloride based)
- Fix water leaks (door seals, trunk, AC drainage)
- Run AC in defrost mode (it removes humidity effectively)
- Clean inside glass (dirty glass fogs faster)
Bottom line
A glass of salt in your car is more of a DIY myth than a real “science-backed hack.” The science (moisture absorption) is real, but the effect is too weak to matter in a vehicle.
If you want, I can share a few actually proven tricks to stop windshield fog in seconds, which drivers use in real conditions.
