Cleaning car windows from the inside: how to get streak-free results

You can clean the inside of car windows with minimal streaking by loosening the film with a suitable glass cleaner, picking it up with a clean cloth, and then going over it again with a second, dry side of the cloth. Cool glass, clean cloths and a small amount of product are crucial. Continuously adding more cleaner to the same dirty side of the cloth often just spreads the film around.

Residue on the windshield is particularly noticeable in low sun or oncoming light. We’ll show you a process that lets you reach the lower corners and then check whether the glass is truly clean.

What do you need for cleaning the inside of the windows?

Have our Glass Cleaner Pro and two clean glass towels ready: one to loosen and pick up the dirt, one for the final finishing pass. Our carbon glass towel is a suitable choice. A towel that has already been used with cockpit care, wax or leather care does not belong on the glass.

Park in the shade and let the glass cool down. Clean dusty interior surfaces in front of the windows first so no dust falls onto the finished glass later. Cover delicate areas on the dashboard with a clean towel and keep cleaners away from screens and electronics.

These instructions apply to accessible real glass. For aftermarket tint films, special coatings or plastic windows, first check the respective care instructions. Suitability for glass is not an automatic approval for every film.

Cleaning the inside of car windows in 5 steps

1. Create access and fold towels

Adjust the seat so you can reach the glass comfortably. Fold the cloths into handy sections with several clean sides. Remove rings or hard bracelets if they might hit trim while you work.

2. Use cleaner sparingly

Inside the car, apply a small amount to the cleaning cloth and spread it over a manageable section of the window. This avoids overspray on the dashboard. The surface should become evenly slightly damp, not dripping. Glass Cleaner Pro should not dry on the surface; on cool glass, allow about 10–max. 60 seconds of dwell time. Work in correspondingly manageable sections.

3. Loosen and pick up the buildup

Wipe in overlapping passes with the towel laid flat. Work right up to the edges. As soon as the towel has picked up dirt, switch sides. With a noticeable greasy film, a second controlled pass with a clean towel surface is better than applying more pressure with an already dirty towel.

4. Follow up with a clean glass towel

Use the second towel to pick up the remaining moisture. Work without heavy pressure until no visible film remains. If this towel also becomes damp or dirty, switch to a fresh one. Two towels are the starting point, not the upper limit, for a few heavily soiled windows.

5. Inspect from several angles

Check from the driver’s and passenger’s seat, using a light held at an angle to the glass if needed. As a final step, wipe the inside, for example, vertically and the outside horizontally: this makes it easier to tell on which side any remaining streaks are. Only inspect the glass when it’s dry.

How to reach the windscreen and the window edges

Clean the windshield in two halves, each from the side where it is easier to reach. Rotate your hand so that the folded cloth lies flat all the way to the lower edge. Do not press through the cloth with fingernails or a hard tool edge.

First lower the side windows a little to clean the upper glass edge. Then close them and clean the remaining inner surface. On rear windows with exposed heating elements, work especially gently; don’t use blades or abrasive tools. 

Why do streaks remain despite using glass cleaner?

• The film moves with every wipe: the towel is often saturated. Use fresh towels and follow up.
• Streaks appear again immediately: Reduce product amount and make sure the glass is cool. Residues from care products in the towel can also be the cause.
• Individual hard spots remain: Do not scrub harder. Check whether the residue is on the surface or if there is damage.

We explain how to remove residues from your towels under How to wash microfiber towels for your car properly. Store clean glass towels separately from towels used with polish or coatings.

Frequently asked questions