How to Defog Your Windshield Quickly with Science, According to a Former NASA Engineer

Keep this trick in your back pocket.

Originally Published: 
foggy windshield
flickr / accarrino

Of all the frustrations that come with winter driving, perhaps the most annoying is when you get into your car ready to go, but realize you can’t see a goddamn thing because the window is fogged up. You try defogging or defrosting it, but you have no idea what will truly help. Hot air? Cold air? Cracked window? A combination? It’s hard to find that perfect equation and there’s likely no real order of operations you follow. So, what is the best way to defog a windshield? Well, former NASA engineer and snowball machine gun inventor Mark Rober decided to figure it out and came up with the perfect method for defogging a window in winter.

In a video posted to his personal channel, Rober shows off his process for figuring out the defogging method. To test out his windshield-defogging hypothesis, Rober puts his skills to work by utilizing the scientific method. First, he created a consistent environment that caused his windshield to be equally blurred for 10 days, so he could test 10 different methods. After the time was up, he found one technique got the job done in almost half the time required by the other nine methods.

Soif you wondering how to defog your windshield as fast as possible, the Robinator swears by this simple 4-step method:

  1. Turn your heat up all the way.
  2. Turn on your AC.
  3. Turn off your air circulation.
  4. Crack open your windows to let air in for a few seconds.

So next time you are running late for work and are ready to lose it because your window is fogged, take a deep breath and remember Rober’s four steps.

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