In order to get the cleanest windows, use an ammonia-free window cleaner and a microfiber towel, according to JD Power. Ammonia-based cleaners can leave streaks on windows even after they are clean.
Using ammonia-free cleaners allows for streak-free results, notes JD Power. Many window cleaning solvents use other chemicals besides ammonia to help remove any hazy sports on the glass.
Using microfiber towels also help keep streaks off the windows. When cleaning a window, spray the solvent onto the surface of the glass instead of the rag, and wipe the dirt from around the perimeter of the glass into its center. Then use another towel to buff off the rest of the window. These methods help keep streaks and blemishes to a minimum.