How Do You Pick a Window Cleaning Robot You Can Trust on the Glass?

Published September 23, 2026 · By the BotLineup editors · Prices and specs as of that date, from the pages under Sources

Summary

Start with safety, not the suction number: how long the robot stays on the glass if power cuts out, and what kind of tether catches it if it lets go. Then make sure it fits your windows, by size and by whether the glass is framed or frameless. Features like auto spray and route planning come last.

Power-loss protection and tethers

A window robot holds itself to the glass by pulling air out with a fan. If power drops, that suction weakens, so most models carry a backup battery that keeps them attached for a while and sounds an alarm.

ECOVACS WINBOT W2 PRO OMNI: a large battery sits in the base station, and ECOVACS says the robot stays on the window for more than 30 minutes even when the charge is low. It uses a 5.5 m combined power-and-safety cable, plus a 1 m safety rope under the station, rated up to 100 kg of tensile strength.
HOBOT-298: its built-in UPS holds it in place for 20 minutes during an outage while it beeps. The safety rope is 4.5 m long and rated for 150 kg of tension.
Yoolax: it has UPS power-off protection and a voice alarm, but the product page doesn't say how long it holds. Yoolax recommends using the safety rope every time.

Will it fit your windows?

The W2 PRO OMNI needs glass at least 30 × 40 cm (11.81 × 15.75 in) and 3 mm thick, and it works on framed and frameless windows. The HOBOT-298 also handles frameless glass, using a laser sensor to find the edge. Yoolax's page doesn't list a minimum window size or frameless support.

For outside panes, figure out where the rope will anchor indoors and whether the power cord reaches an outlet. The HOBOT-298's cord is 4 m long.

Features and price

W2 PRO OMNI ($499.99): up to 5,500 Pa of suction, auto spray, WIN-SLAM 4.0 route planning, and seven cleaning modes. On battery, one charge covers about 110 minutes, or roughly 55 m².
HOBOT-298: automatic ultrasonic mist spray, a cleaning speed of about 2.4 minutes per square meter, and app and remote control. No price is listed on the official page.
Yoolax ($199.99): about 3,000 Pa of suction, dual-side spray that runs automatically or manually, and app and remote control.

Sources

We have not tested these products. Specs, prices, stock and terms are as published on these pages on the date above and can change; check the manufacturer or retailer before you buy.