Short answer: streaks almost never come from the glass itself, but from what you leave behind on it. Here is what white vinegar, methylated spirit and newspaper actually do, and which method comes out on top.
Short answer
Streaks are not dirt. They are a residue left by your cleaning product.
Almost every product leaves something behind: soap residue, minerals from the water, or a thin layer that dries into a haze. Leave the product out, use nothing but water and a densely woven microfibre cloth, and there is nothing left on the glass to dry into a mark. No residue, no streaks.
Why you get streaks on your windows
Because something is left on the glass that then dries: soap, limescale from the tap water, or fibres from your cloth.
Glass is smooth and non-porous. Dirt barely clings to it, which is why you need so little to get it clean. The problem is in the last step: the drying. Anything still lying on the pane at that moment shows up as soon as the water evaporates.
The same three culprits come up again and again. Soap residue that you cannot get off completely. Limescale from hard tap water, which stays behind as a white veil. And fluff from a cotton cloth or kitchen roll.
How the home remedies measure up
They all work a little, and they all have the same problem: they leave something behind.
| Remedy | What it does | Where it goes wrong |
|---|---|---|
| White vinegar | A mild acid that dissolves limescale | Leaves a film you have to rinse off, and the smell is sharp |
| Methylated spirits | Evaporates quickly and cuts through grease | Flammable, gives off fumes in a small room, and is not needed for ordinary dust |
| Newspaper | Absorbs and polishes a little | Modern ink comes off on the window frame and your hands; the old trick dates from a different ink |
| Washing-up liquid | Loosens grease | Leaves a soapy layer that actually attracts dust |
| Squeegee | Pulls the water away in strips | Only works if you have the knack, and water always gets left along the edges |
Do you see the pattern? Every product dissolves something, but adds something of its own that you then have to get off again. That last little step is exactly where the streaks come from.
Do not use vinegar on natural stone
Got marble, limestone or travertine around your windows or in the bathroom? Vinegar is an acid, and acid attacks those types of stone. You end up with dull patches that will never come out. Water is always the safe choice there.
The method that is left standing
If the problem is that products leave something behind, then the solution is simple: leave the product out.
A densely woven microfibre cloth picks dirt up mechanically instead of loosening it chemically. The fibres are split so finely that they get underneath the dirt particles and hold on to them. You damp the cloth slightly, you clean, and nothing is left on the glass to dry into a streak.
No bottle, no rinsing, no waiting. Just water and the cloth, and a pane you look straight through.
How to clean your windows streak-free in four steps
- 1
Pick a cloudy day or the shade
In full sun the water dries faster than you can clean. Then you get streaks, however good your cloth is.
- 2
Make the cloth slightly damp, not wet
Wring it out until it has just stopped dripping. Too much water works against you, because then puddles stay on the glass.
- 3
Work top to bottom in overlapping strips
That way you know where you have been and you see straight away if you have missed a spot.
- 4
Buff it off with a dry side of the cloth
Fold the cloth over to a dry side and go over the glass once more. That is the step that makes the glass truly invisible.
What should you look for in a window cloth?
At the density of the weave and how finely the fibre is split. That decides whether it picks dirt up or only moves it around.
Microfibre is a collective name, not a mark of quality. A loosely woven cloth pushes the dirt ahead of itself and leaves fluff behind. A densely woven cloth with finely split fibres picks it up and holds on to it.
Our magic cloth absorbs up to 7 times its own weight in moisture and removes 99.9% of bacteria with water alone. We make the cloths ourselves, so we decide how dense that weave is.
When should you reach for a drying cloth?
When the surface is genuinely wet, for example a shower screen or a window with condensation on it.
You use the magic cloth slightly damp for cleaning. If it gets wetter than that, the drying cloth is handier: you use that one dry and it soaks up to 800 ml. You can read more about that in our article on the best drying cloth for the bathroom.
Straight to the cloths
The sets most often chosen for windows and mirrors.
- iZi-Clean Magic Cloth, 12 pieces · the best-selling value pack
- Starter pack, 4 pieces · to try it out first
- See all magic cloths
Frequently asked questions
How do you clean windows streak-free without a squeegee?
With a slightly damp microfibre cloth in strips from top to bottom, and then going over it again with a dry side of the same cloth. A squeegee is not needed; it actually leaves water standing along the edges.
Can you clean windows with vinegar?
You can, and white vinegar is the one to use, because it is a mild acid that dissolves limescale. But it leaves a film you have to rinse off, and the smell is sharp. You must not use it on natural stone, because the acid attacks the stone. With water alone you do not have those drawbacks.
Why do I get streaks on my windows?
Because something is left on the glass that then dries: soap residue, limescale from hard tap water, or fluff from a cotton cloth. Without a product and with a densely woven microfibre cloth, nothing is left behind to dry on.
Does newspaper still work for windows?
Less well than it used to. That tip comes from the days of a different printing ink. Modern ink comes off on your window frames and your hands, and the newspaper itself leaves fibres behind.
Which cloth is best for windows?
A densely woven microfibre cloth with finely split fibres. It picks dirt up instead of moving it around. Our magic cloth absorbs up to 7 times its own weight and works with water alone.
Can I clean my windows with water alone?
Yes, and that is exactly the idea. Dirt barely clings to glass, so a densely woven microfibre cloth and water are enough. Without a product, nothing is left behind that could cause streaks either.
When is the best time to clean your windows?
On a cloudy day or in the shade. In full sun the water dries faster than you can clean, and then you get streaks after all.
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