The Fastest Way to Defrost Your Car Windows & Windshield

frost on car windows

We understand that dealing with a frosted windshield isn’t a fun way to start the day, especially if you're on your way to work. Fortunately, your local Glass Doctor has a few tips on how to fight that fog and frost so you can get on to better things.

Learn how to defrost a windshield with these helpful tips:

Why Do Windshields Get Frosty?

Windshields typically get frosty because hot air holds more moisture than cold air. The moisture suspended in warmer air is released when the temperature drops, resulting in condensation. That's why you're seeing all those little water droplets fog up your windshield or turn to ice.

Thankfully, there are several simple ways to defrost your windshield!

How to Defrost a Windshield

Whether you're rushing to work, dropping the kids off at school, or on your way to a weekend adventure, a clear and defrosted windshield is non-negotiable for safe driving.


We recommend following the steps below to defrost windshields and car windows faster.

Step 1: Turn Your Heater On:

Start your engine and use the defroster setting to crank the heater up to the max. Doing so will absorb excess moisture within your vehicle. Remember: hot air can hold more moisture.

Step 2: Press the A/C Button:

Turning on the A/C may sound counterintuitive to the previous step. However, if you live in a humid climate, activating this setting helps dry the air in the vehicle faster with the help of the coils in your air conditioner.

Step 3: Turn Air Recirculation Off:

You need fresh air to enter the car as well. Winter air is cold, and since it does not hold much moisture, it is dry. Bringing cold air into your car ups absorption capacity to quickly dry the saturated air trapped from within.

Step 4: Crack Your Windows:

Cracking your windows helps exchange the humid air in your car with the drier outside air. This method expedites the process of reducing condensation and moisture buildup inside your vehicle.

Step 5: De-ice the Outside of the Windows:

It's also important to defrost your windows while they are defogging. This is an entirely separate process that should never include hot water. Defrosting takes a bit of preplanning but saves you a snow-capped mountain of a headache later.

To begin the process, make a simple solution of 2/3 cup of isopropyl or rubbing alcohol and 1/3 cup of water. Then, pour the mixture into a spray bottle. This solution will not freeze (rubbing alcohol has a freezing point of 138 degrees below freezing). Plus, it can be stored in your car, allowing you to easily spray away windshield ice at any time.

Once you’ve lightly sprayed the mixture onto the affected surface, wait a few seconds for the solution to settle. Then, use a windshield scraper, an ice scraper, or your car's windshield wipers to gently remove the softened ice and frost. Start from the top and work your way down, making sure to clear the entire window for maximum visibility.

How to Defrost the Outside of Car Windows Without Heat

If your heater isn't working or is slow to warm up, don't worry; it's still possible to defrost your car windows fast with the handy de-icing solution described in Step 5 above. Follow the advice listed below, and you'll be on your way to clearer glass in no time.

Quick Solution to Defrost Car Windows

To defrost the outside of your windows without heat, add 2/3 cup of isopropyl or rubbing alcohol and 1/3 cup of water. Then, pour the mixture into a spray bottle. The best part: This solution will not freeze regardless of the temperature in your car.

After gently spraying the solution onto the affected area, wait a brief moment for the mixture to take effect. Following this, use a windshield scraper, an ice scraper, or the windshield wipers of your car to eliminate the softened ice and frost. It’s important to begin from the top and work your way down.

Prevent Frost on Your Windshield & Other Car Windows

The best defense is always a good offense; the most ideal way to defrost your car windows is to eliminate or reduce frost from collecting in the first place.

Here are some tips to help prevent significant buildup on your windows:

  • Park indoors: If possible, leave your car in a covered parking area to shield it from frost formation.
  • Cover your car: Use a car or windshield cover to prevent ice from accumulating overnight.
  • Install a frost guard: A frost guard can be plugged into your car's cigarette lighter socket to generate heat, keeping the windshield ice-free.
  • Use a dehumidifier: Moisture in the car can contribute to frost buildup. Using a dehumidifier can help reduce moisture levels, minimizing accretion.
  • Ventilation: Crack open your windows slightly to allow moist air to escape from the vehicle’s interior, reducing the likelihood of frost collection.
  • Employ a homemade solution: Mix two parts alcohol with one part water and spray it onto the windows the night before frost is expected. The acidity of vinegar can help prevent frost from forming.

Essential Tools for Defrosting Your Car Windshield

If you’re unable to avoid frost accumulation, you should at least ensure you have the proper tools on hand to efficiently remove it from your windows.

Equipment that may prove useful includes:

  • Ice scraper: Scrapers offer a flat blade designed specifically for scraping frost and ice from car windows. They’re among the most common and effective tools for removing frost.
  • De-icing spray: Commercial de-icing solutions can quickly melt the frost on your windshield. These sprays typically contain chemicals that lower the freezing point of water, making the frost easier to remove.
  • Snow brush: Frost can sometimes form in a powdery layer on your windshield. A snow brush with soft bristles can effectively sweep away this loose frost, making it easier to remove the underlying ice.
  • Defroster: Utilize your car's defroster to heat the windshield from the inside, helping to melt frost more efficiently. Combine this with scraping for faster results.
  • Warm water: Pouring lukewarm water over the frosted windshield can help quickly melt the ice. But be cautious that the water isn’t too hot, as it can crack the glass due to sudden temperature changes.
  • Plastic card: While not optimal, we’ve all done this at least once. In a pinch, you can use an old credit or ID card as an improvised ice scraper. Wear gloves if possible, as you’re likely to end up with some frost on your fingertips.

FAQs About Defrosting A Windshield

How can I defrost my windshield quickly?

Some of the more common methods for removing windshield frost include utilizing a scraper, employing de-icing spray, or turning on your car’s defroster. Less optimal measures involve pouring warm water on the window or using a credit card to scrape the buildup away.

Do you defrost the windshield with hot or cold?

Best practices suggest that you should use warm air, not hot air. Hot air can potentially damage the glass due to sudden temperature changes, especially if there are existing fractures.

What is a home remedy for defrosting windshields?

We recommend mixing two parts alcohol with one part water into a spray bottle and applying it to your windows the night before frost is anticipated. The solution’s acidity should help prevent frost from accumulating.

What is the fastest way to melt ice on a windshield?

The best way to ensure an ice-free windshield is to follow our preventative measures and not allow it to form in the first place. The second best method is likely a combination of utilizing your car’s defroster, de-icing spray, and then scraping the ice.

Find a Glass Doctor Professional in Your Local Area

If you're still unsure of how to defrost windshields, your local Glass Doctor® can help. We have specialized tools and decades of experience to clear up your car glass fast. We also offer several auto glass repair, including windshield chip and crack repair, windshield replacements, and windshield protection plans.

Give us a call at (833) 974-0209 to schedule an appointment or for more information.