How to Clean and Remove Water Spots from Auto Glass and Windshields

How to Clean and Remove Water Spots from Auto Glass and Windshields

Updated on June 23 2024

If you spend a lot of time washing your car and waxing the paint, you should also focus on cleaning and removing water spots from the glass windows and windshield. Contaminants like dirt, tree sap, dead insects, and watermarks will also stick to your car’s windows and windshield over time.

You may not notice it at first, but water spots will not only affect driving visibility: It also makes your car look tired and old, even if you have a relatively new vehicle.

Luckily for you, this article will shed light on how to clean and remove water spots (or water stains) from car windows and windshields.

How do I clean my car windows?

Start by washing your vehicle frequently. How often should you wash your car? Automart recommends washing your vehicle at least once every month or once every week, and here’s why: Washing often is more critical if your car spends a lot of time parked outside.

Leaving a dirty car soaking under the hot sun is bad news as the dirt, dust, and road contaminants will literally ‘bake’ into the paint surface and glass, making it harder to remove.

After washing the car, take a few minutes to inspect the windshield and windows. Are there tons of visible water spots and water stains? An easy way to check is to run your palm gently over the glass surface. Does it feel rough to the touch?

If you answered a resounding ‘Yes!’ to both questions, you could eliminate waster spots on the windshield and windows using a few easy steps.

How to Remove Water Spots from Auto Glass and Windshields

The good news is there are many ways on how to remove water spots or water stains from your car’s windows. There are three ways to do it: The lemon juice or vinegar method, the blade method, and the clay bar method.

Tip: Always start with a freshly washed car.

A. Remove water spots using lemon juice or vinegar

Step 1: Apply lemon juice or a vinegar cleaning solution to the glass.

Hard minerals like magnesium and calcium cause water spots to form on the glass as the water evaporates. Water spots are also called calcium deposits or lime scales. Since these minerals are alkaline, the acid in lemon juice or vinegar is enough to dissolve these minerals and keep the glass spotless!

Apply fresh lemon juice directly on the glass and leave it for two to five minutes. You can apply lemon juice using a clean sponge or rub a sliced lemon directly over the glass. Remember that freshly squeezed lemon juice works better than bottled juice.

If you don’t have a lemon in the pantry, you can use a homemade decontaminating solution. Mix equal parts of plain white vinegar and clean water in a spray bottle. Spray the cleaning solution liberally over the windshield and allow it to dwell for up to five minutes.

Step 2: Wipe off the excess with a damp towel.

After soaking the glass in lemon juice or vinegar, wipe off the excess using a damp microfiber or terry cloth towel. Grab a dry towel and buff the glass lightly. If there are still water stains left on the glass, you can repeat the process until the glass is clear.

B. Remove water stains on glass using a blade or scraping knife

Step 1: Apply lubricant to the glass before scraping.

You can use high-quality, ammonia-free glass cleaner as a lubricant when cleaning glass. Spray copious amounts of glass cleaner to lubricate the surface before scraping.

Step 2: Grab a razor blade scraper knife to remove deep-seated dirt and gunk.

Gently run the scraper knife from the top to the bottom of the windshield, making sure to work in small sections per stroke. Notice the gunk accumulating on the blade as you run it over the glass? Those are the deep-seated minerals and contaminants that cause water spots and water stains.

Tip: You can buy a razor blade or glass scraper knife online or from your favorite auto supply store. If you can’t find a scraper knife, you can use a Grade 0000 (yes, that’s four zeroes) wire wool instead. NEVER use sandpaper to remove water spots from glass and windshields. Doing so may cause fine scratches that may prove almost impossible to extract.’

Step 3: Wipe dry with a microfiber towel.

After scraping the glass, remove the excess liquid using a clean microfiber towel. Spray more glass cleaner, turn the towel over, and give it a final wipe.

C. Remove water spots on glass using a clay bar

Step 1: Lubricate the surface with a glass cleaner.

Yes, the same clay bar for paint is also suitable for decontaminating auto windows and glass! Grab a small piece of clay, knead it flat, and you can use it to remove water spots from the windshield. But first, you’ll need to lubricate the windshield with a glass cleaner before proceeding. Spray liberally until the glass is completely wet.

Step 2: Gently rub the clay from top to bottom.

Rub the clay bar from the top to the bottom of the windshield. If the surface begins to dry, do not hesitate to spray more glass cleaner as you proceed.

After cleaning half of the windshield, turn the clay over and knead it again to reveal fresh clay underneath. Do this repeatedly as you clean the side windows and rear windshield to prevent scratching the glass.

Step 3: Wipe the glass with a clean microfiber towel.

After treating the glass with a clay bar, you can remove the excess liquid using a microfiber towel. Next, grab a dry towel and gently buff the glass to reveal a smooth and spotless surface.

Final Step: Apply Rain X or Glass Treatment to Seal the Glass

After cleaning and decontaminating the windshield, the last and final step is to apply Rain X or glass treatment to seal the glass surface. Rain X helps improve driving visibility by repelling water from the glass. It forms a slick barrier on the surface that allows water beads to slide off the glass, similar to how wax protects the paint.

Apply Rain X on a dry sponge and gently rub over the glass, making sure to cover every surface of the windshield. Allow the product to dry to a haze before wiping it off with a damp microfiber towel.

However, Rain X or any other glass treatment will NOT last forever. Depending on existing weather conditions, you would need to reapply or retreat the glass at least once a month.

How do I clean the inside glass in my car?

Automart recommends cleaning the inside glass using an ammonia-free glass cleaner and a microfiber towel. Ammonia is especially harmful on tinted glass and windows. If you cannot find an ammonia-free glass cleaner, using a water and vinegar cleaning solution is your best bet.

Spray the cleaning solution directly on the microfiber towel and wipe the glass clean. Turn the towel over and buff lightly to remove streaks. Repeat until all the inside glass is spotless.


Automart highly recommends decontaminating and deep-cleaning your car’s windows and windshield once every six months. Of course, you can pay a professional detailer to restore the spotless look of your vehicle’s windows, but you can do it at home using basic materials you can find in the pantry.