My nana has always been full of practical wisdom, especially when it comes to keeping a home and car in tip-top shape. One of her favorite household secrets—and one I’ve seen her use countless times—is her method for cleaning car windshields and interior glass. It’s a simple yet powerful trick that always leaves the glass perfectly clean and streak-free.

Watching her clean the windows with such ease and seeing the crystal-clear results inspired me to adopt the method myself. Over time, I’ve learned every step by heart, and I can confidently say that it truly works like a charm. The beauty of this method lies in both its simplicity and its effectiveness, and today I want to share the entire process with you so you can enjoy spotless windows without relying on expensive commercial products. Keeping your car’s glass clean isn’t just about making it look good—it plays a big role in road safety. Clear windshields and side windows improve visibility, reduce glare, and help drivers respond more effectively to their surroundings.

Grime, smudges, and streaks can build up over time and significantly hinder your ability to see, especially during night driving or bad weather. Plus, clean windows make any vehicle look more polished and well-maintained. Nana’s method requires only a few basic materials, most of which you probably already have at home: white vinegar, distilled water, a spray bottle, a soft sponge, and a microfiber cloth. The combination of vinegar and distilled water creates a natural cleaning solution that’s tough on dirt and gentle on glass. First, mix equal parts of white vinegar and distilled water in a spray bottle and shake it to combine.

Then spray the mixture generously onto the windshield and interior glass. Use a soft sponge to gently scrub the surface, paying extra attention to any spots with stuck-on residue or fingerprints. After that, take a clean microfiber cloth and wipe the glass using circular motions. This helps lift away the grime and moisture without leaving streaks. For a finishing touch, use a dry part of the cloth to buff the glass, giving it a glossy, polished finish. The reason this trick is so effective comes down to science. Vinegar is a mild acid that naturally cuts through grease, grime, and mineral buildup.

When paired with distilled water, which has no impurities or minerals that can leave marks behind, the solution dries quickly and cleanly. Microfiber cloths are perfect for this job because their tiny fibers can grab and hold onto dirt and moisture, unlike paper towels which often leave lint and streaks. Compared to traditional glass cleaning products, which often contain harsh chemicals and artificial fragrances, Nana’s method is eco-friendly, budget-friendly, and just as—if not more—effective. It also eliminates the need for separate interior and exterior cleaners, simplifying your cleaning routine and reducing clutter in your car cleaning supplies. To maintain clear glass over time, it’s best to clean your car’s windows at least once a month or more frequently if you live in a dusty area or drive long distances regularly. Try to avoid parking under trees to minimize sap and pollen buildup. Using a sunshade can help keep dust from settling on the interior glass and protect it from UV damage. Always keep a clean microfiber cloth in your glove box for those unexpected smudges that show up between full cleanings. Of course, there are a few common mistakes to avoid. Never use paper towels or abrasive cloths, which can scratch the glass or leave lint behind. Don’t try to clean the glass when your car is sitting in direct sunlight because the solution will dry too fast, creating streaks. Also, make sure your microfiber cloth is clean before you use it; otherwise, you risk wiping dirt right back onto the glass. And remember, gentle pressure is enough—scrubbing too hard could damage the surface of the glass or any protective coatings. People often ask whether this method is safe for tinted windows, and the answer is yes. Because it doesn’t contain any harsh or abrasive chemicals, it won’t harm the tint. Some also wonder if there’s a substitute for vinegar, and while nothing beats vinegar’s cleaning power, lemon juice is a good alternative if you prefer a fresher scent. In the end, Nana’s method is a wonderfully simple way to keep your car windows crystal clear. It’s affordable, easy to do, and kind to the environment—and it really works. Once you try it, you’ll never go back to store-bought cleaners. Clear windows not only make your car look better but also keep you safer on the road, and with this method, achieving them is a breeze.