Choosing the quietest window cleaning robot from makers' figures starts with what each figure covers, and HOBOT's 2S and 298 carry the only one that says where it was taken. HOBOT USA, which sells as HOBOT's authorized US distributor, lists both at "64 dB @1 m" in their specification tables, and HOBOT Technology's own page for the 2S adds "Measured at 1-meter distance." No other window robot maker we read names a distance, a cleaning mode or a test standard.
Ecovacs prints its numbers in headings with no distance: 66dB for the WINBOT W2S PRO OMNI and 68dB for the W2S OMNI, while for the W2 PRO OMNI it says a new duct takes the noise "from 76dB to a minimum of 63dB". Mamibot prints ceilings, and the WINBOT W1 PRO's spec table gives 72 ± 2 dBA. Every one of these figures comes from the suction fan that holds the robot on the glass, which runs for as long as the robot is up. Below, the figures are grouped by the form each maker gives them in, followed by what the manuals say about the fan, the length of a clean and the beeps.
Our picks are listed above, with full specifications for each.
Window robot figures turn up in four forms, and we compare a figure only with others of the same form. None of them names a cleaning mode.
HOBOT is alone here. HOBOT USA, which calls itself the official supplier and authorized distributor of HOBOT Technology in the United States, lists "64 dB @1 m" in the specification tables of both the HOBOT-2S and the HOBOT-298. HOBOT Technology's own pages print no number in their text. The 2S page has a section titled Noise Level with the line "Measured at 1-meter distance." beside a chart of everyday sounds, from a library at 40dB to an airport at 130dB, that gives no number for the robot. The 298 page heads its motor section "Low Noise Design", and the 298's English user manual lists "Noise 64 dB" without the distance; the manual for the older 288 gives that model the same "64dB".
Ecovacs puts two of its figures in headings and one in a spec table:
- WINBOT W2S PRO OMNI: "66dB Silent Work", in a heading and the text beneath it.
- WINBOT W2S OMNI: "68dB silent work, guarding family health", in a heading and on the image beside it.
- WINBOT W1 PRO: "72 ± 2" under "Noise Value (dBA )" in the US spec table.
The first two share a maker, a label and a kind of page, which makes them the closest thing to a like-for-like pair in this category, although Ecovacs does not say they were measured the same way. The W1 PRO's figure is the only one labelled dBA and the only one with a tolerance, so it stands apart from both.
A range from Ecovacs
The W2 PRO OMNI's page says: "The new duct design reduces the maximum airflow velocity and reduces the noise generated from 76dB to a minimum of 63dB." The sentence does not say whether 76dB is the W2 PRO OMNI at its strongest or an earlier duct, and its spec table and manual carry no noise row. The same sentence sits on the page for the older WINBOT W2 OMNI, and a shorter version answers "Can WINBOT work quietly?" on Ecovacs's WINBOT overview, which calls 63dB "similar to a normal conversation". We read 63dB as a floor, not as the sound of an everyday clean.
Ceilings from Mamibot
Mamibot's figures are upper limits. Its W200 SkyBot page gives "Noise Level" as under 65dB, an image on the W120-DP page reads "Tested noise level" under 65Db, and the W300 page gives "≤70dB" in its text and specification list. A ceiling says only that the sound stays below a line, so none of the three is ranked against a value.
Ecovacs gives none for its newest station model, the WINBOT W3 OMNI, or for the WINBOT mini 2, on their US pages, spec tables or US manuals. HOBOT's pages for the S7 Pro, S6 Pro, SP10 and R3 give no figure in their text or spec tables, and its 388 and 300 pages show the same everyday-sounds chart as the 2S, captioned "At 1 meter", again with no number for the robot.
Why the fan runs for the whole clean
A window robot stays up by suction. Ecovacs's overview says WINBOT "uses suction to attach securely to the glass", and the W2 PRO OMNI manual sets out the order: "Press and hold START button on WINBOT for 2 seconds to start the fan", place the robot on the glass, and at the end stop the fan before taking it down. The same manual says "WINBOT's fan cannot operate while charging", so the fan runs only while the robot is working.
None of the makers here describes a setting that turns the fan down for quiet. Mamibot comes closest: it says the W200 SkyBot sets its own suction between 2000 and 2600 Pa according to how dirty the glass is, and raises it at the edge of frameless panes, but it gives one ceiling for all of that. What the makers describe instead is hardware. Ecovacs credits a dual-wing air duct, 6mm acoustic padding and melamine foam for the W2S PRO OMNI's 66dB, HOBOT credits a Nidec brushless motor and metal fan for the 298's lower noise, and HOBOT says the S7 Pro's air channel "redirects the noise to the bottom of the device, reducing harsh, high-pitched sounds".
How long a clean keeps the fan running
Each maker gives a cleaning rate, which is the closest thing to a running time for the noise. Ecovacs lists "1min45s±15s" per square meter in Fast Mode for the W2S OMNI and W2 PRO OMNI. HOBOT gives 2.4 minutes per square meter for the 2S and 298. Mamibot says the W200 SkyBot "finishes 1sqm cleaning in less than 3 minutes". These are each maker's own rates, in different modes, so they tell you how long to plan for rather than which robot finishes first.
The mode changes the running time too. Ecovacs suggests Fast Cleaning for moderately dirty interior windows and Thorough Cleaning, its default, for heavily soiled exterior ones, and it rates the W2S OMNI at about 65 square meters per charge in Fast Cleaning Mode against about 26 in Deep Cleaning Mode. A deeper clean of the same pane keeps the fan on for longer, and Ecovacs prints no noise figure for either mode.
Beeps, alarms and voice prompts
The fan is not the only sound. A window robot is built to make noise when something goes wrong, because it may be hanging from a high window. HOBOT's 298 manual says that without power the robot will "stop automatically, sound an alert, and flash a red light", and its table lists a repeat beep for a power loss, a beep once every 60 seconds for a hardware error, and a single beep for low vacuum pressure or air leakage. HOBOT says the 2S holds on for 20 minutes after a power cut "with audio alert", and the S7 Pro "with continuous audio alert".
Ecovacs's robots speak. The W2 PRO OMNI manual lists its voice prompts in a troubleshooting table and tells owners "Do not panic when WINBOT alarms". HOBOT USA says the 2S app lets you "replace the default voice prompt with any sound of your choice". No maker gives a decibel figure for any alarm or prompt.
What these numbers mean in a room
Ecovacs likens 63dB to "a normal conversation", and the NIDCD gives normal conversation as 60 to 70 dBA, so Ecovacs is placing its smallest figure in the range of ordinary talk. Because decibels are logarithmic, with a rise of about 10 dB heard as roughly a doubling, the 2 dB between Ecovacs's 66dB and 68dB headlines is a small step, and our decibel chart places these levels among everyday sounds.
HOBOT's 1 m is the useful part of its figure, since it is about the distance of someone sitting beside the window while the robot works. No maker says anything about the sound through a wall or a floor, and none gives a figure for the station that winds and stores the cable on Ecovacs's OMNI models.
How we chose
Our starting point was each maker's own site: Ecovacs's US WINBOT pages, spec tables and US instruction manuals, HOBOT Technology's product pages, spec tables and English manuals, HOBOT USA's store, and Mamibot's iGLASSBOT pages, including every image whose caption or file name pointed to noise and the model comparison images on Ecovacs's W3 OMNI page. HOBOT's manual download page loads its list by script, so we read the two English manuals we could reach on HOBOT's own server, for the 298 and the older 288. Cop Rose's domain is listed for sale, Gladwell's store showed only a password page, Liectroux's site did not respond, we found no site for Sweepulire, Alfawise's home page names its S60 and S70 window robots with no product page behind them, and ILIFE's site lists no window robot, so none of these brands is counted.
A robot made the picks only with a figure from its own maker or that maker's authorized US distributor, and the picks run in order of how much the figure says: HOBOT's names a distance, Ecovacs's for the W2S models are plain values in headings, its W2 PRO OMNI claim is a range with an unexplained top, and Mamibot's are ceilings. We copied each figure with its unit and the words around it, noted whether it sat in page text, a spec table, a manual or an image, and set no ceiling against a value. The W1 PRO, the only one labelled dBA, could not be bought from Ecovacs's US store on the day we checked, so it sits among the robots we also considered. Prices are the makers' regular prices on October 17, 2026, with the sale price noted wherever one was showing; Mamibot's site shows none.
We did not measure any of these window cleaning robots; every decibel figure here was copied from the maker's own product page, spec table, product image or manual, or from the specification table of HOBOT's authorized US store.
