Fog is a common problem during the winter months. As we all know, when the cold air outside comes into contact with windows which are heated from inside your car, it creates condensation. This fog can significantly decrease visibility. Plus, it can be a real nuisance when you’re trying to get somewhere on time.

The fastest way to eliminate the fog from your car windows and windshield is a four-step process.

  1. Put the heat on high.
  2. Turn on the A/C
  3. Deactivate the air recirculation
  4. Roll down the car windows

Read on to learn the science behind why car windows fog up and our quick defogging process. Plus, we have some tricks to help you prevent fog from forming on your auto glass in the future.

Why do Car Windows get Fogged Up?

Cold winter weather means a lower relative humidity point. The cool air generally holds less moisture than warm, interior environments. Getting into our cars with wet jackets or snow on our shoes are classic examples of how we further increase the amount of humidity. Then, occupants breathe hot, humid air as they drive along. They might bring a cup of hot coffee on the morning commute, which gives off steam. Then, as the car heats up, the fog forming on the windshield and windows might really start to become a problem for visibility.

How Can I Defog My Windows Fast?

There are just four easy steps to defog the glass in your vehicle super-fast. And these DIY tips are backed by science.

  1. Turn up the Heat – This is the first step. When you first get in your car, turn the heat on at full blast. High heat will help absorb more moisture from the car’s interior.
  2. Turn on the Air Conditioning – The next step is to turn on the air conditioning. This may seem like it would make the foggy windows worse, but it actually helps absorb the excess moisture in the air.
  3. Turn off Air Recirculation – The third step to defogging the windows of the car is to turn off the air recirculation option. This climate control feature can be deactivated by pushing the button that shows a curved arrow inside a car symbol. In order to speed up the process of eliminating moisture, it’s best to draw in cold air from the outside the vehicle. This is because the colder winter air doesn’t hold as much moisture as the car interior which is subject to greater temperature differences.
  4. Crack Open the Windows – The last step is to open the side windows just a crack. It might be uncomfortable and cold for the driver and passengers, but it’s just for a moment. To defrost the windshield quickly, you should open as many windows as possible. That will help replace the more humid air inside your car with the drier outside air.

How Can I Prevent a Foggy Windshield?

Now that you know the easiest way to defog your vehicle windows in a flash, let’s take it one step further. Applying a special product can help you to prevent the windows from fogging up in the first place. There are a few products that you will need on hand to do this, which you can find at your local automotive or car accessory store.

  1. First, you need to clean and prepare the glass. We recommend using a high-quality, ammonia-free glass cleaner and a micro-fiber towel.
  2. Next, you will want to degrease the glass. Use an alcohol-based spray surface cleaner designed to remove oil and lubricants. This will get rid of any traces of grease and prepare the glass for the anti-fog product application.
  3. Then, apply an anti-fog to the inside of the windshield. This product will prevent your windows from fogging up. You will need to spray the product to the micro-suede applicator which comes with it. Just a few squirts directly onto the surface of the applicator should be enough. Wipe the glass with this product, first with vertical strokes, then horizontally. Let it dry as indicated by the anti-fog instructions, for 2 to 5 minutes.
  4. Finally, buff the glass surface with a clean, dry micro-fiber towel.

Leave a Comment