Clean windows or no streaks? Only one product does both well.
Spotless and streak-free windows are all you want from a glass cleaner. However, our test found most can only do one well.
Ammonia is commonly found in glass and window cleaners. It helps a cleaner evaporate, reducing the chances of streaks. The top performer in our test contains ammonia and left glass streak-free.
However, take care when using cleaners containing ammonia. It can strip away coatings such as protective film or tints, including on car windows and eyeglasses. Be careful with metal-framed windows or glass, as ammonia can eat away at the finish. Don’t use it on your computer or laptop screen, as these often aren’t glass.
Most importantly don’t use an ammonia cleaner with a product containing bleach, as mixing them can produce toxic chloramine gas.
One of the biggest causes of streaky windows is residue from the cleaning product itself, so it’s important to remove all the cleaner from a window.
However, if your windows are still left covered in streaks, try these “home hacks”.
Instead of a cloth, clean with scrunched-up newspaper.
Wipe down with paper towels after washing.
Use a squeegee after cleaning.
Dry with a microfibre cloth or use a chamois.
We haven’t tested these streak-free methods, so can’t guarantee how effective they are.
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We've tested 11 glass and window cleaners.Compare glass and window cleaners
Always keep your cleaners away from children — ideally in a high or locked cupboard.
If anyone swallows cleaning product, immediately rinse out their mouth with water and phone your doctor or the National Poisons Centre (0800 POISON).
We’ve assessed how well these products clean. Our test is comparative, which means the products are compared to each other – not to a defined standard of “clean”.
We are developing an assessment of the impact of these cleaners on the environment, and the use of the products with septic tanks and greywater systems.
We’ll update this test with environmental results when we have them. For more information before then, see our article on whether cleaning products green claims stack up.