If you’ve ever stepped into your car and been met with foggy windows and a lingering musty odor, you know how uncomfortable it can feel. These issues are especially common in older vehicles, where moisture can easily build up over time.

Fortunately, there’s a simple and affordable solution that doesn’t require expensive equipment or chemical sprays—it may already be in your home. Salt, a common household ingredient, has powerful moisture-absorbing properties.

It is hygroscopic, which means it naturally draws water from the surrounding air. When placed inside your car, salt helps reduce humidity levels, limiting condensation on the windows and creating a drier interior. This can make a noticeable difference in both comfort and visibility during your daily drive.

In addition to reducing foggy windows, salt can also help address unwanted odors. Musty smells are often caused by excess moisture, which encourages the growth of mold and mildew. By absorbing that moisture, salt helps eliminate the root cause rather than just masking the smell. This can be especially helpful for drivers who are sensitive to allergens or prefer a fresher environment inside their vehicle.

Using salt is simple. Place a small container filled with dry table salt, rock salt, or sea salt under a seat or on a flat surface in your car. Over time, the salt will absorb moisture and may become clumpy, at which point it should be replaced every few weeks.

This easy habit can help maintain a cleaner, more comfortable interior. For older cars that naturally retain more moisture, this method can be especially useful. It supports better air quality, improves visibility, and helps keep the cabin feeling fresh and dry.