The best glass cleaner is going to provide you with streak free results every time.
You have some choices to make aside from which brand to buy! Window cleaners
come in foaming and liquid forms, each promising perfect streak free results.
The problem is some of these products fall short on that promise.
Some of the streakiest windows I have seen have been done by very popular glass cleaning products. Apply too much and there will be streaks, use too little and there will be streaks! So you may find that it takes some trial and error to find a product that works best for you.
If you don't want to get lost in a sea of glass cleaning products you can make
your own. Vinegar and water works well. Simply add a small amount of
vinegar to a spray bottle filled with water and you are good to go!
For me, the best method I have come across doesn't include using any glass cleaner.
All that is needed is water and new microfiber cloths. Using new or near new
cloths will provide you with the best results. Older cloths just don't absorb
moisture as well.
For this method, water and clean microfibers are all you need!
Its simple, wet one cloth with water and ring it out enough so its not dripping.
Wipe the window down with the wet cloth then buff it dry with a dry microfiber.
When buffing, make sure the cloth is folded. Once one side gets too damp
or dirty, flip it over to a clean dry side and continue buffing until the window
If your wet cloth becomes too dirty, or is no longer wet enough, you will need
to rinse it off again. This is to prevent applying grime to the glass when you
are cleaning the remaining windows.
For really dirty glass you may have to repeat the cleaning procedure for best results.
The combination of clean microfiber cloths and clean water will produce great
results every time.
If you decide to use a store bought glass cleaner, I still highly recommend using clean, new microfiber cloths to achieve the cleanest glass possible.