How to clean sunglasses without scratching the lenses

To clean sunglasses without scratching them: rinse the lenses under lukewarm running water first, wash with a single drop of plain dish soap, rinse again, and dry with a clean microfibre cloth. That is the entire method, and it is the same for polarized lenses. Almost every scratch on a lens comes from one of two mistakes: wiping a dry lens, which drags grit across it, or using the wrong cloth or chemical. Skip both and a lens stays clear for years.

The method, step by step

1. Rinse. Hold the glasses under lukewarm tap water for a few seconds, lenses and frame. This floats off dust, sand and salt before anything touches the lens. Not hot water: heat can lift coatings and warp plastic frames.
2. Soap. Put one small drop of plain dish soap on each lens. Rub gently with clean fingertips, both sides, and along the frame and nose pads where skin oil collects.
3. Rinse again. Until the water runs clear and the lens does not feel slippery.
4. Shake and dry. Shake off the drops, then dry with a clean, dry microfibre cloth. Use light pressure. Do not scrub.
5. Check. Hold the lens up to a light. Smears mean soap residue or a dirty cloth; rinse and repeat with a fresh cloth.

Thirty seconds. It works on any lens material and any coating.

What not to use

• Paper towel, tissue, napkins. Paper is made of wood fibre and it is abrasive. It is the most common cause of fine scratches.
• Your shirt. It carries dust, and the dust does the scratching.
• Window cleaner or anything with ammonia. Ammonia degrades anti-reflective and mirror coatings.
• Alcohol wipes, acetone, nail-polish remover. Solvents attack coatings and can craze some plastic lenses.
• Saliva. Unhygienic and does nothing.
• Hot water. Can lift coatings and warp frames.
• Dish soap with lotion or "moisturising" additives. Leaves a film. Plain is the only kind to use.

Why rinsing first matters most

A scratch needs something harder than the lens dragged across it. Lens materials are soft; sand and mineral dust are hard. A dry wipe pushes those particles across the surface under pressure. Rinsing lifts them off first, so the cloth only ever touches a clean, wet surface. It is the single habit that separates lenses that last from lenses that fog with hairline scratches in a season.

Cleaning polarized sunglasses

The method is identical. There is nothing to add and nothing to avoid beyond the list above. What differs is what is at stake. In a laminated lens, like tri acetate cellulose, the polarizing film is sealed between two layers and cannot be washed or worn off; the only way to damage it is to scratch through the outer layer. In a lens where the polarization is a surface coating, that coating is the outermost layer and every scratch goes through it. Either way, rinse first.

Our lenses are laminated; the about page explains the construction and our post on how to tell if a lens is polarized includes a check you can run after cleaning to confirm nothing has changed.

Mirrored lenses

A mirror coating sits on the outer face and is the most scratch-prone part of any lens. Everything above applies with more care: no dry wiping, ever. The Ice Blue and Dark Blue mirrors on this site are the pairs to be most careful with.

On the go

If you are away from a tap: a spray bottle of water, or a lens spray sold as safe for coated lenses, plus a microfibre cloth. Spray the lens wet, then wipe. The rule is still the same one: never wipe dry.

Keep the cloth clean. A microfibre cloth that has been in a pocket for a month is full of grit. Wash it, without fabric softener, every few weeks.

Frames and nose pads

Skin oil and sunscreen build up on the frame and nose pads and can discolour clear pads. The same soap and water handles both. A soft toothbrush cleans the hinge and the groove where the lens sits; while you are there, check the hinge screw is snug, and see our loose sunglasses post if it is not.

Frequently asked questions