Eureka J20 Ultra robot vacuum cleaner

Eureka J20 Ultra review: Innovative mopping but incomplete

The Eureka J20 Ultra aims to deliver a robust cleaning performance with enhanced features compared to its predecessor, the Eureka J12 Ultra. The Eureka J20 Ultra introduces a reeling mop, which is truly innovative. Unlike the SwitchBot S10, its mop is able to cover a larger surface and get rid of stains more efficiently.

Considering the J20 costs more than $1,000, it is poised to compete with flagship robot vacuums like the Dreame X40 and Roborock S8 MaxV Ultra. In this detailed review, let’s explore if it’s worth considering and how it compares to the competition.

Eureka J20 Ultra

Vacuuming efficiency
Mopping efficiency
Obstacle avoidance
Battery life
Value for money
Design & build quality


The Eureka J20 Ultra offers robust cleaning with an innovative reeling mop system and 8,000Pa suction power. It effectively cleans most surfaces and excels in mopping with its built-in detergent cartridge. However, its bulky design and less user-friendly app are drawbacks. Navigation and obstacle detection are decent but could be improved. It also lacks the advanced features to clean along baseboards and corners other products offer. Overall, the J20 Ultra is a strong performer with advanced mopping capabilities but has some limitations in design and usability.

At Smart Home Critic, we help you find the right smart home product for your needs. To ensure fairness and depth, we test every product rigorously for at least a week by a minimum of two reviewers, who have to agree on the final rating. Please refer to our review policy for more information.

Bulky dock with basic design

The Eureka J20 Ultra features a bulky dock, measuring 423x462x452.5mm. It also includes a built-in compartment for a detergent cartridge, allowing it to automatically add cleaning solution. The water tanks and dust bag are directly accessible from the top of the station for easier refill and empty.

The robot itself comes with a slightly squared shape, diverging from the more common circular design seen in many robovacs. On top, a LiDAR dome sits alongside two buttons for quick and easy operation. Beneath the removable cover, the dust bin and HEPA filter are easily accessible for hassle-free maintenance. On the underside, it features a single bristled brush roller and a reeling mop. The latter is liftable, preventing wetting carpets when passing over them.

The design, while not the most aesthetically pleasing, is practical and utilitarian. The build quality is decent, but given the price, I was expecting something more refined.

Limited and Unappealing App

The Eureka app falls short compared to market leaders. It’s usually slow to open the robot’s page. This creates a frustrating experience when you want to start a quick cleaning cycle.

It features a dark and stark design that is less user-friendly than apps from Roborock and Dreame. During initial use, the robot maps your home to create a map. Its precision in room separation can be lacking, but the maps are editable. It also allows for the saving of multiple maps, which is helpful for multi-story homes.

You can direct the robot to clean specific rooms or zones, as well as the entire home. The app offers various cleaning modes: vacuuming, mopping, vacuuming and mopping simultaneously, or vacuuming followed by mopping.

It also provides options to adjust suction power and mop washing frequency, along with dock settings such as dust emptying frequency and mop drying duration.

Overall, the app is straightforward but lacks advanced customization and features. It also doesn’t display obstacles on the map, despite the robot’s obstacle avoidance technology.

Impressive suction but not top-tier

The Eureka J20 Ultra delivers solid vacuuming performance with its 8,000Pa suction power. It provides effective cleaning on both hard surfaces and carpets. Although this suction power is decent enough, it falls short of some flagship models that offer over 10,000Pa.

The J20 Ultra’s bristled brush roller, combined with the side brush, ensures efficient debris collection, tackling dust, pet hair, and crumbs with ease. The robot’s unique shape enables it to navigate and clean corners more thoroughly than many traditional circular models. However, it doesn’t come with a flexible side brush like the latest flagships from Dreame and Roborock, which can clean corners precisely.

The vacuum performs well on hard surfaces such as hardwood and tile, efficiently picking up debris. The 8000Pa suction power is generally sufficient for most surfaces, including carpets. If you have high-pile carpets, though, a model with two rollers and a higher suction power would provide even better results.

Effective mopping

A standout feature of the J20 Ultra is its reeling mop system, which keeps the mop pads continuously moist for more effective cleaning. This system, combined with the built-in detergent cartridge in the dock, significantly enhances the robot’s mopping performance. The ability to dispense detergent ensures that the mops are always ready with the right cleaning solution, improving stain removal capabilities, especially on stubborn stains.

On lightly soiled floors, the J20 Ultra performs admirably, efficiently removing stains and dirt. It also tackles tougher stains well, applying a 17N force during cleaning to ensure thorough dirt removal.

However, the Eureka J20 Ultra does miss out on a few features that are becoming standard in the market. For instance, it does not heat water to wash the mop pads, which could make the overall cleaning experience less hygienic. Additionally, despite its unique mop system and shape, it struggles to mop effectively along baseboards and in corners, which is a notable drawback.

Decent navigation but limited obstacle detection

The Eureka J20 Ultra does a decent job when it comes to navigation. However, it sometimes struggles with positioning itself accurately within a room. For instance, it got stuck trying to clean the kitchen baseboards, not realizing it was too tall to pass properly. It also tends to miss a few spots or pass several times over the same one, which isn’t what I’d expect from a flagship robot.

When it comes to obstacle detection, the J20 Ultra has its shortcomings. Despite being equipped with Dual 3D obstacle detection technology, it often fails to detect low-lying obstacles, especially cables. This has led to several issues. The worst is definitely finding the robot stuck on my dog’s tail, which has never happened before with any other robot. The J20 also struggles with some furniture legs, trying to pass over them. It’s very surprising, as the robot otherwise senses taller objects precisely and avoids them without other issues.

Reasonable noise and battery life

The J20 Ultra operates at a noise level that is generally manageable during daily activities. While it is slightly louder compared to some other robot vacuums, the noise remains within a tolerable range. You can still work or have conversations, although it might be a bit distracting when watching TV. Overall, the noise is not overly disruptive but can be noticeable in quieter settings.

In terms of battery life, the J20 Ultra offers up to 130 minutes of cleaning time on a full charge. While this is not the longest battery life available for a robovac, it is sufficient for covering moderately sized areas and completing its cleaning cycle without needing frequent recharges. If the battery runs low during a cleaning session, the robot can automatically return to the dock to recharge before resuming its task, ensuring a seamless cleaning experience.

Low but messy maintenance

The Eureka J20 Ultra is designed with ease of maintenance in mind, though it has some shortcomings. The dock’s baseplate is not fully removable, which can make thorough cleaning a bit challenging. Additionally, soiled water often remains at the bottom of the dock, making it hard to clean manually.

The reeling mop system reduces the frequency of manual cleaning for the mop pads, thanks to its self-cleaning feature. However, for better hygiene, it’s still recommended to machine wash the mop pads occasionally.

The bristled brush roller can be a hassle to maintain, as hair tends to get tangled and wrapped around it. Regular maintenance and occasionally cutting out tangled hair are necessary, which makes the J20 Ultra less ideal for homes with pets or long hair.

Emptying the dustbin and cleaning the filters is straightforward. The dock automatically empties the robot’s bin into the dust bag, minimizing the need for manual intervention. Refilling and emptying the water tanks is also simple, thanks to the built-in handles and tall, narrow shape. However, the app lacks a dedicated cleaning mode, which could have streamlined the maintenance process further.

Should you buy the Eureka J20 Ultra?

The Eureka J20 Ultra offers a range of advanced features that make it a strong contender in the robot vacuum market. Its reeling mop system and built-in detergent cartridge enhance its mopping performance, and its 8,000Pa suction power delivers solid vacuuming results on most surfaces. However, it does have some shortcomings, such as a less user-friendly app, navigation issues, and a noise level that might be slightly disruptive in quieter settings.

While the J20 Ultra performs well overall, the lack of features like heated water for mop washing and better obstacle detection may be a dealbreaker for some users. Given its price point, it competes with high-end models but falls short in certain areas. If you prioritize advanced mopping capabilities and can overlook some of its limitations, the Eureka J20 Ultra is worth considering. However, if you need a more polished experience with fewer compromises, exploring other flagship models might be a better option.

Innovating reeling mopNo corner and baseboard cleaning
Overall good cleaning performanceNavigation and obstacle detection
Built-in detergent cartridgeNo hot water mop washing


What makes the Eureka J20 Ultra’s mop system unique?

The Eureka J20 Ultra features an innovative reeling mop system. This differs from most robot vacuums that use sonic, rotating, or flap mops.

Is the Eureka J20 Ultra’s suction power sufficient for high-pile carpets?

The Eureka J20 Ultra has an 8,000Pa suction power, which is effective for most surfaces, including carpets. However, for high-pile carpets, a model with higher suction power and dual rollers may be more suitable.

Does the Eureka J20 Ultra use hot water for mop washing?

No, the Eureka J20 Ultra does not use hot water for mop washing.

How effective is the Eureka J20 Ultra at cleaning corners and baseboards?

The Eureka J20 Ultra struggles to mop effectively along baseboards and in corners. It doesn’t have extending or flexible brushes or mops to clean along baseboards and corners.

Kyle Lakewood

Based in New York, Kyle combines his passion for smart home products with a commitment to honest, unbiased reviews. As the founder of Smart Home Critic, he guides readers in choosing the right products for their needs. Living with his partner and dog, Kyle brings a personal touch to his work, involving his whole family in the review process to ensure each product is thoroughly tested and family-approved.