Vacuum Wars is reader supported. When you make a purchase using links on our site we may earn a commission. Details.
  1. /
  2. Robot Vacuum Reviews
  3. /
  4. Dreame X40 Ultra Review: Is...

Dreame X40 Ultra Review: Is This The Best Robot Vacuum?

Dreame has been on a roll lately releasing numerous robot vacuums this year, but the X40 Ultra robot vacuum mop combo stands out from them all. After weeks of using and evaluating our Dreame X40 Ultra, it’s clear that this model surpasses previous models and outperforms the robot vacuum we recently crowned as the best. In this Dreame X40 Ultra review, we’ll dive into the details of this exceptional machine, including its features, pros, and cons.

Dreame X40 Ultra
The Dreame X40 Ultra is a powerhouse among robot vacuums, combining exceptional suction power, advanced mopping capabilities, and innovative features. With its 12,000 Pascals of suction, it easily outperforms its predecessors and competitors. The advanced mop system, edge cleaning capabilities, and impressive obstacle avoidance also add to making it a versatile and efficient cleaning tool. Plus, the comprehensive app and new pet-friendly features add convenience and customization to its use. Overall, despite the higher price tag, the Dreame X40 Ultra offers tremendous value and would make an excellent choice for practically any home.
  • Impressive debris pick-up on hard floors and carpets.
  • 12,000 Pa suction
  • High-performing obstacle avoidance
  • Advanced mopping
  • Washes and dries mop pads
  • Edge sweeping and mopping
  • Lifts or removes mop pads
  • Full-feature app
  • Pet-friendly features
  • Premium cost range
We earn a commission if you make a purchase, at no additional cost to you.
06/18/2024 06:10 pm GMT

Box and unit of Dreame X40 Ultra Robot Vacuum and Mop with Auto-Empty and Mop Self-Cleaning, displayed on a table with accessories, in a room with various vacuum cleaners on shelves.
Dreame X40 Ultra Robot Vacuum at our studio © Vacuum Wars

Dreame X40 Ultra review: performance and evaluation

For our Dreame X40 Ultra review, we put it through various real-world assessments to determine its performance, and it performed impressively well.


The Dreame X40 Ultra’s power is impressive. Dreame claims it has 12,000 Pascals of suction, significantly more than its predecessor, the X30 Ultra. And we more or less confirmed Dreame’s claim in our bench evaluations. 

This model scored significantly higher in both suction and airflow evaluations than the X30 and surpassed the average scores by a wide margin.

Comparison chart of suction power in kPa for Dreame X40 Ultra, Dreame X30 Ultra, and average of 90+ tested models, with the X40 Ultra scoring 1.03, the X30 Ultra scoring 0.34, and the average being 0.68.
Suction power comparison — Dreame X40 Ultra vs. Dreame X30 Ultra © Vacuum Wars
Comparison chart of airflow in CFM for Dreame X40 Ultra, Dreame X30 Ultra, and average of 90+ tested models, with the X40 Ultra scoring 20, the X30 Ultra scoring 11, and the average being 16.
Dreame X40 Ultra’s airflow blows away the competition © Vacuum Wars

Carpet deep clean

In our practical performance evaluations, the X40 Ultra far exceeded expectations. Notably, it did phenomenally in our carpet deep clean evaluation, which measures its ability to pick up deeply embedded debris such as sand in carpets. 

Comparison chart of carpet deep clean test scores for Dreame X40 Ultra, Dreame X30 Ultra, and average of 90+ tested models, with the X40 Ultra scoring 80, the X30 Ultra scoring 71, and the average being 77.
Dreame X40 Ultra excels in deep carpet cleaning © Vacuum Wars

As you can see, the X40 Ultra outperformed the X30 and surpassed the average scores out of 90+ evaluated robot vacuums, which is a significant improvement.

Despite Dreame’s advancements in features and navigation, their last few models have lagged in power and performance metrics, scoring below average in our evaluations. However, the X40 Ultra marks a change, now offering the power to complement all those impressive features.

Debris pick up

The X40 Ultra also excels at its primary task of sweeping up debris from hard floors and carpets. It delivers nearly perfect results, equipped with a single-side brush and a main silicone brush in a floating brush housing.

Bottom view of the Dreame X40 Ultra robot vacuum, showing its brushes, mop pads, and wheels.
A close-up look at the Dreame X40 Ultra’s efficient cleaning mechanism © Vacuum Wars

It effectively picked up everything from fine to extra-large debris on both surface types, meeting the high expectations for a robot in this price range.

Hair pick up

It also performed well at picking up pet and human hair. However, longer hair did tend to get tangled in its brush, which is unfortunately quite common for robot vacuums.

Dreame X40 Ultra robot vacuum features

Edge cleaning

The Dreame X40 Ultra robot vacuum has a swinging side brush designed for improved corner cleaning, which performed decently in our evaluations. It also features an automatic extending mop pad that swings out, enhancing its ability to clean edges effectively.

Top view of the Dreame X40 Ultra robot vacuum cleaning a corner of a hardwood floor.
Dreame X40 Ultra tackles corner cleaning with ease © Vacuum Wars

Advanced mop system

When it comes to mopping, the X40 Ultra is one of the most advanced robot mops we’ve evaluated. Its mopping ability was awe-inspiring in evaluations involving things like the dried-on coffee and grape juice stains, where it visibly outperformed the Roborock S8 MaxV

Side-by-side comparison of the Roborock S8 MaxV and Dreame X40 Ultra cleaning dried grape juice from a white surface, showing the performance of each robot vacuum.
Dreame X40 Ultra vs. Roborock S8 MaxV © Vacuum Wars

While both models have great mops, the Dreame X40 Ultra, with its spinning pads, seems more effective for tough stains, although a more objective evaluation method is needed.

Also, the robot vacuum mop combo can lift its mop pads up to 10.5 mm when it senses carpets to avoid getting them wet. That means you should be able to do a single run in your home if you have a mix of hard floors and carpets. 

One unique feature we’ve only seen on Dreame robot vacuums is the magnetic pads. When enabled in the app, the X40 will leave the mop pads on the base, vacuum the carpets first, and then return to the base to retrieve the pads for cleaning hard floors.

Dreame X40 Ultra robot vacuum in its base station, showing the feature for detailed carpet care.
Achieve detailed carpet care with the Dreame X40 Ultra’s smart mop removal

The X40 Ultra also has a brand new feature, which is it lifts its front side brush upon detecting a wet spot to keep it dry. 

Side view of the Dreame X40 Ultra robot vacuum showing its brush and side brush lifting mechanism
Effortlessly tackle wet and dry messes with Dreame X40 Ultra’s advanced brush lifting

There’s also a Robo swing feature that enables it to mop hard-to-reach areas. 

Dreame X40 Ultra robot vacuum using MopExtend RoboSwing technology to clean under low furniture
Cleans under low furniture with is using the X40 Ultra’s MopExtend RoboSwing

Additionally, when it spots particularly bad stains using its camera, it will give those areas extra attention while mopping.

Advanced base station

One of the Dreame X40 Ultra’s biggest advantages is its advanced base station. It automatically empties the dustbin into a large 3.2 L disposable bag, washes the mop pads with hot water, dries them with hot air, and fills the mop tank with fresh water and a cleaning solution of your choice. The trend towards non-proprietary solutions is a welcome development.

Dreame X40 Ultra robot vacuum docked in its base station against a white background.
Dreame X40 Ultra docked in its sleek and powerful base station © Vacuum Wars

The base station also includes the innovative self-cleaning system introduced with the Dreame X30 Ultra, which uses a gear-driven mechanism and squeegees to wash the bin. It also features a sensor in the dirty water line that detects if the mop water is dirty and triggers another mop-washing cycle if necessary. 

Obstacle avoidance

Regarding obstacle avoidance, the X40 Ultra features an impressive system that uses a camera, a structured light system, multiple lasers, and an LED light. While these components are standard, Dreame must be doing something right.

That’s because all of their recent models are tied for the top three spots for obstacle avoidance in our evaluations. Not to mention, the X40 is the second robot vacuum to achieve a perfect score.

Comparison chart of obstacle avoidance scores for Dreame X40 Ultra, Dreame X30 Ultra, Dreame L30 Ultra, Dreame L20 Ultra, and average of 90+ tested models, with the X40 Ultra scoring 12, the X30 Ultra scoring 11, the L30 Ultra scoring 10, the L20 Ultra scoring 10, and the average being 9.
X40 Ultra leads in obstacle avoidance © Vacuum Wars

That’s not to claim it will flawlessly avoid every small obstacle like Legos. However, it significantly reduces the need to pick up items beforehand, making it one of the most reliable robot vacuum options available.

Battery efficiency and navigation

In our various navigation and battery life evaluations, the X40 Ultra did very well, providing near-perfect coverage of the new floor plan without getting stuck. 

Comparison chart of obstacle avoidance scores for Dreame X40 Ultra, Dreame X30 Ultra, Dreame L30 Ultra, Dreame L20 Ultra, and average of 90+ tested models.
X40 Ultra outshines competitors © Vacuum Wars

It was fairly efficient, covering right around the average number of square meters per minute. Plus, it has one of the largest batteries in the industry, at 6,400 milliamp hours. Dreame claims it can run for 194 minutes on low power and cover over 3,300 square feet per charge.

In our “best settings” run—using standard power with carpet boost and mopping features enabled—the Dreame X40 Ultra achieved 1.96 minutes per percentage point, which is above average. 

Comparison chart of battery efficiency for Dreame X40 Ultra and the average of 35+ tested models, with the X40 Ultra scoring 1.96 minutes per percentage and the average scoring 1.47 minutes per percentage.
Exceptional battery performance from the Dreame X40 Ultra © Vacuum Wars

This means it can clean even very large floor plans in a single run. Additionally, it offers recharge and resume functionality, fast charging, and supports multi-level maps, making it highly versatile and capable of handling extensive cleaning tasks.


The Dreame X40 Ultra’s app is comprehensive and user-friendly, offering near-total control over every aspect of the robot’s behavior. You can adjust mopping settings, manage auto-bin emptying, and configure obstacle avoidance. The app also includes various mapping features, including virtual barriers, 3D mapping, room and zone cleaning, and advanced scheduling options.

Screenshots showing various features and settings of the Dreame X40 Ultra robot vacuum app.
Comprehensive control with the X40’s advanced app settings © Vacuum Wars

Pet features

Several new pet-friendly features are also available. The X40 offers two-way video calling, allowing for remote interaction with pets. 

Hand holding a smartphone showing remote video supervision and voice interaction with a pet through the Dreame X40 Ultra app.
Interact with your pets remotely using the Dreame X40 Ultra’s video and voice features

It will also intelligently suggest pet zones to avoid food bowls and boost suction power around cat litter boxes for more effective cleaning.

Cons of the Dreame X40 Ultra

While the X40 Ultra is super impressive, it’s not perfect. There’s just one potential drawback to consider.


It surpasses the Roborock S8 MaxV as the most expensive robotic vacuum evaluated so far, though the difference isn’t substantial. Other than that, the robot vacuum is practically perfect.

Dreame X40 Ultra Review: value and final thoughts

The Dreame X40 Ultra has indeed taken the top spot in our algorithm based on evaluation scores and features. 

However, we’re not going to declare it the best on the market just yet, especially with a new flagship contender from Ecovacs scheduled for evaluation in the coming weeks. Final opinions on the best flagship robot vacuum for the spring or summer season will be reserved until then. 

Nonetheless, the Dreame X40 Ultra sets a high bar and will be tough to beat. If you want a robot vacuum mop combo that’s powerful, efficient, and packed with many useful advanced features—the X40 may be right for you.

Vacuum Wars

Other Related Resources from Vacuum Wars

Best of the Best

Current Vacuum Wars product rankings:

Best Cordless Vacuums
Best Robot Vacuums
Best Upright Vacuums
Best Carpet Cleaners
Best Air Purifiers