Most people clean their glasses several times a day. Almost all of them do it in a way that slowly ruins their lenses. If your glasses never seem fully clear, or you keep noticing faint scratches that weren’t there last year, the cleaning method is usually the cause — not the glasses.
Here’s how to clean your glasses properly, what to avoid, and why a dry cloth is doing more harm than you think.
Why dry wiping scratches your lenses
The problem isn’t the cloth. It’s what’s on it. The moment a microfiber cloth picks up dust, it carries tiny mineral particles. Those particles are harder than the coating on your lenses.
Anti-reflective coatings sit around 4 to 5 on the Mohs hardness scale. Everyday dust and grit reach 6 to 7. So every time you wipe a dry, dusty lens, you’re dragging something harder than the coating across it. The scratches are microscopic at first. Over months, they add up to the permanent haze you eventually blame on “old glasses.”
The right way to clean glasses by hand
If you’re cleaning manually, do it wet. This is the method opticians recommend:
- Rinse first. Run your glasses under lukewarm water for a few seconds. This washes away loose dust before anything touches the lens.
- Use a drop of dish soap. A small amount of lotion-free washing-up liquid on your fingertips, gently worked over both sides of the lens and the frame.
- Rinse again. Make sure all soap is gone.
- Dry with a clean microfiber cloth. Only on a wet lens, and only a cloth that’s actually clean — not the one living in your pocket.
Avoid hot water (it can damage coatings), glass cleaner with ammonia, paper towels, and tissues. All of them either strip coatings or scratch.
What hand-cleaning still misses
Even done perfectly, manual cleaning has a blind spot: the frame. The hinges, nose pads, and the seam where the lens meets the frame collect oil, makeup, and bacteria that your fingers can’t reach. You can have a spotless lens sitting in a dirty frame.
This is exactly why opticians don’t hand-clean glasses behind the counter. They use an ultrasonic cleaner.
How ultrasonic cleaning solves both problems
An ultrasonic cleaner fills a small tank with water and sends high-frequency vibrations through it. Those vibrations lift dirt off every surface at once — lens, frame, hinges, nose pads — without anything ever touching the glass. No wiping means no scratching.
Lensio brings that same method home. You add water and a tablet, drop your glasses in, and press once. Three minutes later they come out cleaner than a cloth could ever get them, with the coating fully intact. We tested it specifically on AR, HEV and UV coatings so it cleans deep without damaging the layers you paid for.
The short version
- Never dry-wipe dusty lenses — it scratches the coating.
- If cleaning by hand, rinse, use a drop of lotion-free soap, rinse, then dry with a genuinely clean cloth.
- Hand-cleaning can’t reach the frame, where most bacteria hide.
- Ultrasonic cleaning removes dirt from every surface without contact — the safest method for coated lenses.
Your glasses are the one thing you look through every waking hour. Clean them in a way that keeps them clear for years, not one that quietly wears them down.