Frosch Glass Cleaner Spirit Review: 6–7 Windows Tested

Hands-On · 6–7 Windows Cleaned

★★★★★4.1/5

My test: 6–7 home windows · first bottle · October 2026

I paid: €1.85 for 500 ml on October 3, 2026 at Dofted · historical price

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Paid link · Amazon US listing; price and shipping may differ from my local purchase

Frosch Spirit Glass Cleaner — 4.1/5: good results, too much runoff

Quick verdict: 4.1/5. I got very good cleaning results for €1.85: fingerprints, greasy marks and everyday dirt came off easily, with fewer streaks than my previous supermarket glass cleaner. The weak point is the thin, watery spray. It runs down the pane and collects at the bottom, adding a cleanup step.

Best for: Budget-conscious window cleaning where a little runoff is not a deal-breaker.

Skip if: You prefer a spray that stays put or a foamier product with less liquid to catch at the bottom. I personally prefer the Sidolin cleaner I have used.

What I like

• Very good everyday window cleaning for the €1.85 I paid
• Fewer visible streaks than my previous unnamed supermarket cleaner
• Fairly quick drying on the glass
• Pleasant, neutral-feeling clean scent
• Reliable spray trigger and easy dosing

What could be better

• Thin liquid runs down the glass instead of staying where sprayed
• Extra wiping is needed at the bottom edge
• Not as easy to work with as the foamier Sidolin product I have used
• My Sidolin cleaning result looked a little better; see my separate first-hand Sidolin Cristal review. Neither cleaner was tested in a controlled head-to-head experiment.

Bottom line: 4.1/5. A good-value glass cleaner I am satisfied with, but I probably would not buy it again because I prefer how Sidolin applies and how the finished window looks. That preference does not mean Frosch performs badly.

How I tested Frosch Spirit Glass Cleaner

I purchased one 500 ml bottle with my own money on October 3, 2026 and cleaned approximately six or seven different windows in my home. This is an early hands-on review after real window cleaning, not a long-term durability study. I plan to clean windows perhaps twice a month, but I have not been using this bottle on that schedule yet.

How well does Frosch clean windows?

For normal household window dirt, it worked very well. Fingerprints, greasy marks and general grime came off without difficulty in my use. The glass looked clean afterward, and I noticed fewer streaks and smears than with the previous glass cleaner I bought from a local supermarket. I do not remember the name of that older cleaner, so I cannot make a brand-specific comparison.

I did not have to go back and wipe the whole pane again after cleaning, and the glass dried fairly quickly to my eye. I did wipe the bottom edge, though, because liquid ran downward and collected there. This distinction matters: the glass result was good, but the application process was messier than I wanted.

The biggest drawback: watery spray and runoff

The Frosch liquid felt noticeably more watery and less foamy than other cleaners I have used. Instead of staying on the area I sprayed, a fair amount ran down the glass. That left liquid to catch and wipe away at the bottom. I would prefer a slightly foamier spray that stays put while I work.

This is my observation about how the product behaved during my cleaning sessions—not a measured viscosity or foam-retention test. I also cannot say whether every cloth, spray distance or amount of product would behave exactly the same. The manufacturer advises using an appropriate amount of cleaner and wiping with a dry cloth; lighter dosing may help limit unnecessary runoff.

Streaks, drying and final appearance

I was pleased with the final appearance: fewer visible marks than my older, unnamed supermarket cleaner, and drying seemed reasonably fast. I did not count streaks, photograph a standardized before/after grid or time evaporation with a stopwatch. Reflections, sunlight and viewing angle can also make window marks easier or harder to see.

My Sidolin cleaner seemed to leave the glass looking a little cleaner and was easier to work with because it foamed better. That is a genuine preference based on my use, but I have now published my separate first-hand Sidolin Streifenfrei Cristal review based on approximately six windows cleaned in one session. I am not claiming a controlled head-to-head winner here.

Spray bottle, scent and handling

The trigger mechanism worked fine. I had no problems with the bottle, and I found it easy to spray and dose. The scent was pleasant: clean, fairly neutral and not something I found bothersome. The issue was the consistency of the liquid on the window, not a defective nozzle.

Because I have used only my first bottle for a small number of cleaning sessions, I cannot assess how the trigger holds up over many refills or months of use.

Is €1.85 good value for a 500 ml bottle?

Yes, based on my purchase. I paid €1.85 for 500 ml at Dofted, equivalent to €3.70 per litre before any delivery cost. That is the price I personally paid on October 3, 2026, not a live Amazon price. For that amount, I received effective cleaning, reasonably quick drying, a working spray trigger and a pleasant scent.

The drawback is the extra attention needed at the bottom of the pane. If you want the cheapest cleaner that gives a good-looking window, I can see the appeal. If you care more about easy application than saving a small amount, I would compare other formulas before deciding.

My weighted 4.1/5 rating explained

This is my own editorial score, not an Amazon average. I weighted actual cleaning most heavily, then streaking and application. Because I have only recently bought this bottle, I have not invented a long-term durability score. The figures are judgment-based scores from my stated experience, not instrument readings.

Calculation: (4.3 × 0.40) + (4.4 × 0.20) + (3.0 × 0.20) + (4.5 × 0.05) + (4.8 × 0.15) = 4.145, rounded to 4.1/5. For the site-wide approach, see How I Test. The cleaning and price scores reflect my limited use and the €1.85 I paid.

Frosch versus Sidolin: which would I buy again?

I am satisfied with Frosch, but I probably would not buy it again. In my own use, Sidolin foamed better, was easier to work with, and appeared to leave the window slightly cleaner. The exact variant was Sidolin Streifenfrei Cristal 500 ml; see my published Sidolin review for the full first-hand account. This remains an informal comparison, not a controlled head-to-head test.

For readers choosing between them, my practical decision is simple: Frosch wins points for the low price I paid and solid cleaning. Sidolin is my personal preference for application and finish. For the bottles I bought, Sidolin cost €1.95 and Frosch cost €1.85 for the same 500 ml size, so Sidolin was €0.10 more expensive. I nevertheless preferred Sidolin’s foam and finish.

What is in Frosch Spiritus Glass Cleaner?

Frosch describes the 500 ml Spiritus cleaner as an alcohol-based formula for glass and many wipeable surfaces. Its published ingredient overview lists less than 5% anionic surfactants, plus alcohol and food colorant. These are manufacturer statements, not results from chemical analysis in my home. Frosch also states that the product is microplastic-free and uses recycled/recyclable packaging. I did not independently verify those environmental claims.

The manufacturer’s usage guidance says to spray and wipe with a dry cloth. Follow the label on your own bottle and avoid inhaling spray mist. Frosch’s regional product guidance also warns against use on LCD/TFT screens and varnished wood; I have only tested windows.

Who should buy it—and who should skip it?

Consider it if you need inexpensive glass cleaner for occasional household windows and want a decent result without much fuss. At my €1.85 purchase price, it is easy to understand why someone would choose it.

Look elsewhere if you dislike watery sprays running down a pane, or if you want a formula that clings to the glass more like foam. I personally prefer Sidolin, despite being satisfied with the Frosch cleaning result.

Frequently asked questions

Final verdict

4.1/5: a good glass cleaner for the price I paid. Frosch removed everyday dirt and fingerprints effectively, smelled pleasant and gave me fewer streaks than my previous supermarket cleaner. The thin liquid that runs down the window is the reason I cannot rate the experience more highly. I am happy with the result, but Sidolin is currently my preferred glass cleaner.

Sources and review transparency

This review is based primarily on my own purchase and cleaning experience. Product and ingredient context: Frosch official Spirit glass cleaner page; usage and surface restrictions: Frosch Denmark product information; exact listed Amazon variant: Frosch Spiritus 500 ml, ASIN B0BCWLKX2K. The paid short link was provided for this product but its redirect could not be independently verified; the linked Amazon product identity is based on the separately verified listing. No manufacturer, retailer or third party paid for this review.