Roborock S4 Robot Vacuum Cleaner Review - Not to be messed with

Pros & Cons | Price | Features | Design | S4 vs S6, S5 Max, Xiaowa E2, Xiaowa E3 | and more...
Robot Vacuum Roborock S4
Updated: 20th Dec 2019
Published: 24th Sep 2019
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By SHN Team

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Searching for an answer? Here's our table of contents: 

1) Summary

2) Design Overview

3) Basic Information/Specifications

4) Features

          a) Deep Down Cleaning 

                    i) High Suction Power

                    ii) Floating Main Brush

                    iii) Dynamic Speed Side Brush

                    iv) Air Filter

                    v) Zigzag Cleaning Pattern

                    vi) Automatic Cleaning

                    vii) Manual Cleaning

          b) Navigation Technology and Intelligent Mapping 

                    i) Revamped Drivetrain

                    ii) Intelligent Sensors

                    iii) Creating Virtual Barriers

          b) Power 

                    i) Battery

                    ii) Charging

5) Comparison of the S4 and Other Roborock Robot Vacuum Cleaners

          a) Roborock S4 vs Roborock S6 

          b) Roborock S4 vs Roborock S5 Max 

6) Roborock S4 vs S5 vs S6 vs S5 Max

          a) Navigation 

          b) Brushes 

          c) Suction 

          d) Mopping 

          e) Control 

7) Roborock S4 vs Roborock Xiaowa E2

8) Roborock S4 vs Roborock Xiaowa E3

9) Verdict

10) More specifications

Price: See offer on Amazon US. UK and EU prices to follow. 


  • Great price for what you get
  • Intelligent cleaning in both automatic and manual mode
  • High-precision laser navigation
  • Good battery life power
  • Good suction


  • Due to its high suction power, it can pick up small toys if they happen to be strewn on the floor
  • No mopping capabilities - but expected to be at the lower price end, so we can see why


The S4 from Roborock is the latest in the company's line of flagship vacuum cleaners. it features noteworthy design improvements and technological upgrades over previous versions.

In this review, we take a look at its design, features and cleaning performance. We will also make comparisons between this model and the company’s previous models.


The Roborock S4 vacuum cleaner uses a combination of technological advancements to tackle complex homes. One of the top challenges that robot vacuums face is the issue of navigation.

According to the company co-founder and vice president, Simon Wan, Roborock continually examines user perception of its line of products. With that in mind, every new model seeks to solve real-life issues that consumers face.

“With the S4 we looked to tackle the issue of navigating furniture head-on, so consumers can trust that it will always finish the job, even when they’re not home,” he explains.

To address this issue, the model makes use of intelligent navigation and advanced mapping. Furthermore, it features a technology that allows it to free itself from obstacles. Coupled with its intense cleaning capabilities, this means that it delivers on all fronts.

Additionally, the design is ideal for all kinds of home, making it a one-of-a-kind, all-around robot vacuum cleaner for smart home enthusiasts.


Design Overview

The vacuum cleaner sports a modular design and measures approximately 350mm in circumference and 96mm in height. Sporting a protective rubber bumper, it can handle bumping into objects without any risk of damage.

It comes with a combination of brushes for different cleaning needs and varying environments. A noise-reduction air screen ensures minimal interference as it works.  When the juice runs out, it is also capable of automatically recharging and resuming cleaning from where it left off.

A total of 12 sensors offer superb navigational capabilities, and four of these sensors are cliff sensors that prevent nasty falls, say from a flight of stairs.

Read also:

Roborock S6 MaxV vs. S6 vs. S5 Max vs. S5 vs. S4 vs. E2 vs. E3

Roborock S6 MaxV review

Roborock S5 Max

Basic Information/Specifications

Take a look at some of the basic features of the S4:

  • Dustbin Capacity – 420 ml
  • Weight – 3.8 kg
  • Run Time – Balance Mode up to 150 min; Quiet Mode up to 180 min
  • Cleaning Area – 250 square metres
  • Battery – 5,200 mAh
  • Obstacle Crossing Ability – up to 1.5 cm
  • Charging Time – less than 6 hours
  • Maximum suction – 2,000 pa
  • Voltage – 58W


  1. Deep Down Cleaning

Cleaning is the main objective of any vacuum cleaner, but this model takes it to a whole new high.

  • High Suction Power

To start with, its suction power is second to none; it can lift up objects as heavy as AA batteries. This makes it a breeze to lift dirt and dust from deep within carpet fibres as well as from hard floors.

It also features an innovative airflow design that keeps suction strong at all times, including when the dustbin gets full.

  • Floating Main Brush

The second highlight of its cleaning abilities has to do with the design of the main brush. As a floating brush, it adapts its height to suit different settings. For instance, when cleaning hard floors, it drops close to the floor. On the other hand, it lifts when cleaning carpets for agitation purposes.

In addition to adapting its height to the environment, the main brush has an impressive cleaning ability. Consisting of a combination of rubber fins and standard bristles, it can handle any surface with ease and the amount of dirt it can pick up could leave you dumbfounded.

  • Dynamic Speed Side Brush

Furthermore, it sports a side brush that is capable of adapting its cleaning speed. This feature comes in handy when targeting tricky corners. In such a setting, the brushing accelerates to propel dust into its cleaning path. But when it is away from walls, it decelerates to limit the tendency to propel dust all over the room.

  • Air Filter

Using its air filter, the bot traps dander, mould and all other particles that may be lodged in a carpet or on a hard floor.

  • Zigzag Cleaning Pattern

To cap it all, the vacuum cleaner uses a Z-motion for its cleaning pattern. Before it initiates the cleaning process, it will map out the space based on the edges of the room. It then zigzags across the floor to reach all areas and clean efficiently.

  • Automatic Cleaning

As a smart robot vacuum cleaner, the S4 can make itself busy while you are away from home. For this convenient automated cleaning, you need to set a timer. But alternatively, you can simply press a button on the app to initialise it.

  • Manual Cleaning

You also have the option of manual cleaning, which you can operate via a remote control on the app. This includes controls set in the form of a joystick to send the bot to specific areas on the map.

An alternative to using the joystick control is placing a pin on the map and telling the bot to “go there.”

As mentioned at the onset, this device is ideal for cleaning complex homes. Here are the features that make this possible.

  • Laser Distancing

The bot makes use of a technology known as laser distancing navigation. This is a high-precision system that scans the target room at 300 RPM. The bot then uses the feedback to create a real-time map of the space, which is accurate up to +/-2 cm.

Equipped with this map, it can easily travel between surfaces and free itself from furniture and tight corners. It can also offer selective and targeted vacuuming when necessary.

In addition to aiding the bot in navigation, the map also offers other significant benefits. To start with, it makes it possible for the device to keep track of the areas it has already cleaned. You can also use it to identify problem areas that pose navigational challenges.

It is possible to edit this map to suit a specific room as well as set up zones to create a scheduled cleaning system. For instance, you may not want the bot to suck up a child’s toys or interrupt your kitten’s sleep.

You can also access the map to assess whether cleaning was thorough, as it keeps a log for every cleaning session. If you want the bot to clean using a previous schedule, you can even easily restore a map for that purpose.

  • Revamped Drivetrain

To avoid getting trapped in objects, the robot features a revamped drivetrain. The drivetrain prioritises reverse power so the device can easily back away from obstacles.

  • Intelligent Sensors

Another major highlight of the technology behind it has to do with the sensors. 11 of its 12 sensors work together to provide the vacuum cleaner with fall avoidance. They also offer carpet boost, contribute to its anti-entrapment abilities and provide height sensitivity.

  • Creating Virtual Barriers

Additionally, you can select specific areas to clean by placing virtual barriers or no-go zones. Doing this is quite straightforward using the Mi Home app which works seamlessly with both Android and iOS devices.

  1. Power

Another impressive feature of this gadget has to do with its massive power capacity.

  • Battery

The Roborock S4 comes with the most powerful battery in its class of vacuum cleaners. This is a 5,200 mAh lithium-ion power pack that is capable of driving the device for up to 3 hours. The actual length of time it takes to run flat will depend on the cleaning mode.

In Quiet Mode, it will run non-stop for the said 3 hours. However, if you use the more power-intensive Balanced Mode, it will last up to 2.5 hours, which is still remarkable.

The Quiet Mode is ideal for early morning or late-night cleans as it emits the least noise. But even on the max power mode, it is not a loud vacuum cleaner.

  • Charging

Considering the size of the battery, charging takes a considerable period of time. When the battery is fully drained, you may need slightly less than 6 hours to get it to capacity.

Comparison of the S4 and Other Roborock Robot Vacuum Cleaners

Roborock S4 vs Roborock S6

Prior to the launch of the S4, the S6 was the most recent and most advanced bot cleaner in the Roborock line of products.

One of the main differences between the two has to do with the navigation. Though both feature high-precision laser mapping, the S4 offers some distinct advantages. Its sensors offer advanced anti-entrapment capabilities.

Furthermore, its drivetrain has a focus on reversing, making it easy for the bot to dislodge from tight corners and furniture. This means that it rarely gets stuck and will always get the job done.

However, the S6 also doubles as a mopping bot, while the S4 focuses solely on vacuum cleaning.

See Roborock S6 deal on Amazon US and Amazon UK

See Roborock S4 deal on Amazon US

Roborock S4 vs Roborock S5 Max

Roborock S5 Max, which launched recently, is an improvement over the previous version, S5. Unlike the S4, which is purely a vacuum cleaner, this is part robot vacuum cleaner and part robot mop.

Just like the S4, it can pick up items as heavy as AA batteries and offers automatic docking and charging mode. It also has a similar battery capacity and features automatic carpet detection for higher suction power.

But unlike the S4, which has a matte finish, it comes with a glossy finish that easily gets marked by fingerprints and smudges.

See Roborock S4 deal on Amazon US

Roborock S4 vs Roborock S5

The Roborock S5 has been around a long time and is still a highly versatile cleaner. It features a battery with a similar capacity to the S4’s. As such, it can clean for up to 150 minutes. But it does not have the Quiet Mode feature on the S4 which allows for longer cleaning times.

Like the S6, the S5 has mopping functionality, which is not present on the S4.

Another difference between the two has to do with aesthetics. The S5 came with a glossy finish, which looked great, but would easily get smudges. But the S4 has a matte finish which looks even better.

The S5 also had physical buttons, which are not as sleek-looking as the touch buttons on the S4. Doubtless, the mapping and navigation technology on the S4 is also way ahead of the S5, providing a more seamless cleaning experience.

See Roborock S5 deal on Amazon US and Amazon UK

See Roborock S4 deal on Amazon US

Roborock S4 vs S5 vs S6 vs S5 Max

Roborock S4, S5, and S6 are all highly effective vacuum cleaners, but all of them come with certain unique features and capacities. Roborock S4 has extremely advanced smartphone compatibility and focuses entirely on vacuuming. Roborock S5 and S5 Max don’t have an adaptive routing algorithm so they can’t automatically calculate the best route to clean, but they have an effective mopping function so it can first wipe the floor with a wet cloth. Finally, S6 has all of the features you could ask for along with an enhanced navigation system and an effective brush roll. So let’s look at each of these Roborock vacuum cleaners and their capabilities in isolation.


Roborock S4 was the first in the bunch to use LIDAR (light detection and ranging) technology for navigation. With this technology, S4 emitted pulsed laser emissions to accurately calculate its distance from other objects so there’s no collision. S4 also introduced a stronger drivetrain so it could navigate with greater stability and use the extra throttle to get out of difficult situations.

However, Roborock S5, S5 Max, and S6 also incorporated these features so they’re just as capable as the S4. What sets them apart, however, is that they also have better wheels that allow them to climb higher by up to 2 centimeters and with greater stability. S5, S5 Max, and S6 also have advanced sensors that allow them to slow down in certain areas to prevent collisions and avoid objects with greater precision.

All things considered, Roborock S4 deserves applause for introducing a lot of advanced navigation systems. But Roborock S5, S5 Max, and S6 are faster, better, more accurate, and they include greater infrared sensors — 13 and 14. So if you’re looking for maximum accuracy, go for the Roborock S6 or S5 Max.


All Roborock vacuum cleaners — S4, S5, S5 Max, and S6 — come with an anti-tangle brush roll that moves with rubber blades and they have a brush roll that floats over the floor’s height. All of them also include a side brush with five fins with an automatic adjustment of rotating speed. However, the S6’s brush roll is a lot thicker and denser, which means it’s more capable of sweeping up debris and cleaning floors. It’s also made of durable silicone, which makes it tangle-free in operation. As such, Roborock S6 has the best brushes with stronger cleaning capacities.


All Roborock vacuum cleaners — S4, S5, S5 Max, and S6 — generate 2,000 pascals of suction force. However, S5, S5 Max, and S6 also come with an automatic suction-boost function that uses a pressure sensor to detect the surface material and adjust the suction force accordingly to pick up objects without damaging carpets. Roborock S6 is also quieter than the others by a few decibels. As such, all Roborock vacuum cleaners are equally effective in suction, but if you have a lot of carpeted areas, you may need the S5, S5 Max, or S6.


Roborock S5, S5 Max, and S6 come with a specific mopping function. When you activate this feature, these vacuum cleaners will release a wet mop to wipe the floor clean. Roborock S5 and S5 Max come with two reusable microfiber pads while S6 comes with 10 disposable washcloths and a microfiber cloth.

Roborock S5 and S6 can also hold 140 millimeters of water while the S5 Max can hold 280 millimeters of water — they also include a bionic system to steadily release water only while the robot is in motion. Roborock S5 and S6 use a pair of capillaries to control the water. And S5 Max is a lot more advanced with a squeeze pump and a sensor that allows it to modify the water flow depending on the type of floor. All things considered, Roborock S5 Max is the best mopping vacuum cleaner but S5 and S6 are also good enough for those who don’t have too much hardwood surface in their home.


All Roborock vacuum cleaners are compatible with smartphones, are voice-enabled, and can be controlled via smartphone apps. All of them allow you to set schedules, manually drive the robot, adjust suction force, or create zones. While all the Roborock robots allow you to save at least one map, the S5 Max and S6 also allow you to store three maps with specific schedules and suction details. With the S5 Max, you can also control which areas it should mop, which areas it shouldn’t touch, and control the exact level of water flow. All things considered, all Roborock vacuum cleaners can be controlled via the smartphone and have most of the same features — but S5 Max and S6 allow you to set three maps and S5 Max also has advanced mopping options.

Roborock S4, S5, and S6 are all highly effective vacuum cleaners, but all of them come with certain unique features and capacities. Roborock S4 has extremely advanced smartphone compatibility and focuses entirely on vacuuming. Roborock S5 and S5 Max don’t have an adaptive routing algorithm so they can’t automatically calculate the best route to clean, but they have an effective mopping function so it can first wipe the floor with a wet cloth. Finally, S6 has all of the features you could ask for along with an enhanced navigation system and an effective brush roll. So let’s look at each of these Roborock vacuum cleaners and their capabilities in isolation.

Roborock S4 vs Roborock Xiaowa E2

The E2 is also a 2-in-1 robot vacuum, but unlike the S-series models, it is a budget version. Offering a combination of vacuuming and mopping features, it weighs only 3 kg and is thus lighter than the S4.

Its battery capacity is lower, at 2,600 mAh, and it has physical buttons as opposed to touch controls, as is the case with the S4.

Like the S4, you can control it using the Mi Home app as it has no physical remote control.

See Roborock E2 deal on Amazon US and Amazon UK

See Roborock S4 deal on Amazon US

Roborock S4 vs Roborock Xiaowa E3

The E3 is a high-tech model sporting a sleek finish in spite of its low-key aesthetic. Its battery capacity and suction power are at par with the S4.

This model also offers simultaneous sweeping and mopping and has touch controls. However, unlike the S4, which cleans in a zigzag pattern, this model cleans in a straight line.

The E3 can have difficulties reaching the bases of walls and corners, a problem that the S4 addresses with its innovative brush design.

Its mapping feature is also not as advanced as the S4’s, and it requires a magnetic strip for creating no-go zones.

See Roborock E3 deal on Amazon US

See Roborock S4 deal on Amazon US

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Roborock S4 vs S5 vs S5 Max vs S6 vs E2 vs E3

  Roborock S4        Roborock S5 Roborock S5 Max Roborock S6 Roborock Xiaowa E2 Roborock Xiaowa E3
Colours Black Black, White, Beige Black, White Black, White, Beige Black, White Black, White
Adaptive Route Algorithm Yes   Yes Yes    
Selective Room Cleaning Yes   Yes Yes    
LDS Laser Navigation Yes Yes Yes Yes    
High Precision Map Yes Yes Yes Yes Yes  
Map Saving Yes Yes Yes Yes Yes  
Zone Cleanup Yes Yes Yes Yes Yes  
Real-Time Robot Location Yes Yes Yes Yes Yes Yes
App Navigation Yes Yes Yes Yes Yes Yes
Voice Navigation Yes Yes Yes Yes Yes Yes
Dual Electronic Compasses         Yes Yes
Inertial Navigation         Yes Yes
Mopping Function   Yes Yes Yes Yes Yes
Auto-Recharge Yes Yes Yes Yes Yes Yes
Top-Up Charging   Yes Yes Yes Yes Yes
Over-the-Air Upgrades Yes Yes Yes Yes Yes Yes
Do Not Disturb Yes Yes Yes Yes Yes Yes
WiFi Connectivity Yes Yes Yes Yes Yes Yes
Voice Pack Yes Yes Yes Yes Yes Yes
Washable Dustbin Yes Yes Yes Yes Yes Yes
Washable E11 Air Filter Yes Yes Yes Yes Yes  
Volume (Balanced Mode) 59db 62db 62db 58db 62db 62db
Battery Capacity 5200mAh 5200mAh 5200mAh 5200mAh 2600mAh 5200mAh
Suitable Area >200㎡ >200㎡ >200㎡ >200㎡ 120-150㎡ 150-200㎡
Rated Power 58W 58W 58W 58W 54W 57W
Dustbin Volume 420ml 480ml 460ml 480ml 640ml 640ml
Suction 2000Pa 2000Pa 2000Pa 2000Pa 1800Pa 2000Pa
Runtime 150 minutes 150 minutes 150 minutes 150 minutes 100 minutes 150 minutes


Looking at the features of the Roborock S4 and comparing it to previous models makes it clear that this is a solid choice. It offers great performance in areas such as navigation, anti-entrapment, mapping and automated cleaning.

It has an appealing aesthetic and the innovative design minimises the risk of damage from bumping into objects or falling off high surfaces. Overall, it is a great choice for every smart homeowner looking for a combination of performance and innovation.

More specifications

Basic Information

Product Size

354.7 x 350 x 96mm

Package Size

489 x 403 x 152mm



Navigation System

Laser Distancing Navigation

Max. Suction

2000 Pa


58 W

Dust Bin Capacity

420 ml



Run Time

up to150 min (Balanced Mode)
up to 180 min (Quiet Mode)


5200 mAh

Cleaning Area


Charging Time

6 hours

Obstacle Crossing Ability

Up to 1.5 cm







Hardware and Design

Modular Design

Floating Main Brush

Protective Rubber Bumper

Detachable Main Brush

Dynamic-speed Side Brush

Automatic Recharge and Resumption

Noise Reduction Air Screen

Edge Cleaning Ability

Consistently maintains a 10mm

distance when cleaning along walls








Types of Sensors


Number of Cliff Sensors


Ability to detect if filter is in position

Ability to detect clogged filter








Zone Cleaning

Designated Cleaning

Real-time Mapping

Scheduled Cleaning

Setting virtual barrier/ zones in-app


Reader Reviews

Roborock S4

Only got mine two days ago, but it's going well so far
I got the S4 two weeks ago.. for the price it's really good value!
I love my S4, but it gets stuck on my large rug, so I have to move it


I have the S6, love it! Think it will be more expensive though.