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Roborock S4 Review

Derek Hales

Written By: Derek Hales

Updated on:

UPDATE – The Roborock S4 has been discontinued. Its nearest replacement that’s still sold is the Roborock S4 Max.

The Roborock S4 was just released. But how does it perform and is it worth the money? Let’s find out now.

Smart & Budget-Friendly Robot


Roborock S4

The Roborock S4 is the newest robot to join the Roborock family. It’s similar to the S5 and S6, while adding a new reverse capable drive-train, but dropping the mopping attachment. Compatible with the new Roborock app, it’s incredibly easy to use featuring no-go zones, advanced navigation, great cleaning performance, re-charge and resume, and more. It scored an average of 96% in our cleaning tests, making it one of the best robots we’ve tested to date at this price point. A solid value overall.Check Price


  • Updated drive-train with reverse capability to eliminate object or furniture entrapment
  • App abilities allow for “No-Go zones” or specific spot cleaning
  • Excellent cleaning performance, 96% across all of our tests
  • Sweet spot between performance, usability, and price


  • Does not include mopping mode and attachment like Roborock S5 and S6

Note on Models & Names

Roborock’s model and naming process can be hard to decipher. So it’s easier to understand, we created a handy guide to clear up any confusion. To learn more about the model and naming process and get the correct option, check out the Roborock review and comparisons here.

Roborock S4 Design

The design of the Roborock S4 is similar to the prior models, the Roborock S6 and Roborock S5. It includes a small bump out on the top which houses the navigating sensor.

Roborock S4 robot vacuum cleaner

To control the robot vacuum, there are buttons on the top as well for easy access, even if the vacuum is in motion.

Navigation sensor on top of the S4
Navigation sensor on top of the S4

Unlike other models, the Roborock S4 is only available in one color, black gloss.

What controls are on the top?

Keeping with the familiar design of the other models, the S4 has two buttons that control the unit.

Roborock S4 top control buttons
Control buttons on top of the S4

These are located towards the front of the vacuum on the top, easily accessible whether the vacuum is in use or on the charger. Similarly, the laser navigation system is still in the center of the vacuum, behind the control buttons.

Here is how the buttons are used to control the robot vacuum:

  • Power on / off (hold the power button)
  • Start / pause the current cleaning cycle (press the large power button)
  • Send to charger (press the home button)

What’s on the bottom of the vacuum?

The bottom of the vacuum has been revamped since the Roborock S6 model was made. 

Button of the Roborock S4
Button of the Roborock S4

What stayed the same?

Similar Features

  • Edge sensors: to prevent the vacuum from “driving” off edges like stairs (The S4 has been upgraded to 11 total edge detecting sensors).
  • Contact sensors: intelligent feature that communicates to the vacuum that contact has been made with the charging station and it is charging properly.
  • Spiral main brushroll: centrally located in the middle of the vacuum with bristles for agitating and collecting debris directly into the cleaning path (The S4 now has a floating brushroll to adapt to changing floor heights, like going from hardwood to carpet).
  • Wheels: there is a small steering wheel in the front of the vacuum used to maintain balance and 2 large wheels for navigating over obstacles (up to 2cm).
Roborock S4 wheels
Roborock S4 wheels

There are some notable upgrades in the Roborock S4. 

The S5 model came with a 3-legged soft bristle side spinning brush, which is pretty standard for most brands of robot vacuums we’ve tested. The S6 saw an upgrade to 5-legged rubberized sweeper without bristles.

Roborock S4 rubber spinning side brush
Roborock S4 rubber spinning side brush

The S4 model has the same rubberized sweeper, but now it adapts its speed. It accelerates when cleaning along corners but slows down when out in the open to reduce debris being dispersed around the room.

Roborock S4 brushroll
Roborock S4 brushroll

We noted similar cleaning performance in both the S6 and S5 models last time, even with the upgrade in the S6.

See our Roborock S5 review here and Roborock S6 review here.

Our cleaning results of the S4 were similar on hardwoods, slightly better on low pile carpet, and notably better on high pile carpet compared to the S5 /S6. While it lacks a few features, most notably mopping, the solid cleaning performance means it’s a great value.

Continue below for our extended cleaning tests and data.

Cleaning Modes

Unlike the S6 and S5 models, the Roborock S4 does not have mopping abilities. This means there are only 4 cleaning modes instead of five.

Roborock S4 cleaning modes
Roborock S4 cleaning modes – accessible only with the app

Still, it allows for a customized vacuuming experience, regardless of floor type, so it can be used in the whole house or apartment:

  1. Standard mode: Use for standard multi-surface cleaning from hardwoods and low-pile carpet to high-pile shag carpets. The updated features and powerful suction power are great whether you’re vacuum hard or carpeted surfaces.
  2. Silent mode: A great option when a quieter decibel level is needed, Silent Mode isn’t truly silent, but it’s notably quieter than the other cleaning modes.
  3. Turbo mode: When needed, Turbo mode provides maximum suction power.
  4. Medium mode: Medium mode is a suction power mode between standard and turbo.

Size & Dimensions

Compared to other available robot vacuums, the Roborock S4 is similar in size, weight, and height. Here are the S4’s specific dimensions:

  • Diameter: 13.8″
  • Height: 3.5″
  • Weight: 8 pounds
Roborock S4 size

Accessories & Parts

The Roborock S4 comes fully equipped to get started right away using the robot vacuum.

All initial accessories and parts are included in the box, with minimal assembly required. Depending on your needs, some accessories may not be used or needed.

Roborock S4 HEPA filter
1 of 2 HEPA filters included with the S4

What’s in the box?

Here is a list of everything included in the box with the Roborock S4:

  • Charging station: provides a centrally located place for the vacuum to recharge between cleaning cycles
  • Cleaning tool: used to maintain optimal performance, clean out the crevices of the vacuum between cleaning cycles
  • Spiral brushroll: the main cleaning component used to agitate and collect debris on all floor types, even high-pile carpets, spinning constantly as it moves along the floor surface. Only includes 1 spinning brush (no replacement).
  • Dust bin: houses dry dirt and debris captured as it moves along floor surfaces during cleaning cycles
  • HEPA filter: washable and reusable filter located in the dust bin that traps pet dander, dust, mold and other particulates while cleaning. 1 HEPA filter is installed and 1 replacement is included.
  • User manual: information on use, care, and troubleshooting the Roborock S4 is included in the user manual

RELATED – Want to see other robot vacuum reviews? Check out more here

Roborock S4 features

The Roborock S4 is on par with other high-end robot vacuums, with upgraded features for a satisfying cleaning experience. 

Though it doesn’t have the mopping feature like the S5 and S6 models, it still packs some nice features.

Roborock S4 profile view

Let’s take a look at what’s included in this model:

App Control

The wifi-enabled S4 connects to both the Roborock and Mi Home Apps, allowing for easy control from any smartphone. We used the Roborock app in our tests.

Use the app to:

  • Start / stop a cleaning
  • Send the robot back to the charging base
  • View digital map
  • Draw “No Go Lines” for custom boundary cleaning
  • Establish zones or send the robot to a particular spot

Smart Navigation & Mapping

The Roborock S4 includes laser precision accuracy in its navigation system. It scans the room at 300 revolutions / minute, using that information to map out each room’s dimensions to +/- 2 cm.

The app allows you to name specific rooms so the S4 can automatically recognize a room. A schedule can also be created using rooms names.

Roborock app cleaning map
Cleaning map generated by the S4 after cleaning our photography studio

When cleaning, the S4 uses a Z-shaped pattern around the edges before cleaning the rest of the room in a zigzag pattern.

As the S4 cleans each room more and more, algorithms work to create a more efficient cleaning path with less chance of missing spots.

Cleaning maps called “digital map reports” are generated and viewable. It’s easy to see where the robot cleaned and if any spots were overlooked.

Recharge & Resume

This feature is similar to one used by Roomba robot vacuums. It ensures a thorough clean each time, regardless of battery life.

Roborock S4 on charging base

The S4 will vacuum around the room until it detects the battery getting low. When it does, the vacuum will automatically return to the charging station, stay there until fully charged, and then resume the cleaning cycle where it left off.

This is a great feature especially in large areas, reducing missed spots and uneven cleaning.

No-Go Zones

Use the app to tell the Roborock S4 where cleaning is not needed and to create virtual barriers.

Roborock app no go zones
You can create no go zones and virtual lines to block the robot from entering certain areas

You can choose a “No-Go Zone” for any reason, whether an entire room or just a specific area in a room. The S4 will avoid that section, just like the S6 model.

This is a feature also found on the Neato Botvac D7 Connected.

Cleaning Performance

To be able to make a fair assessment on cleaning performance, we do testing at both the Modern Castle lab as well as high-traffic areas of my personal home.

We use three types of floors:

  • Hardwood floors
  • Low-pile carpet
  • High-pile carpet

We spread the following items along each type of flooring to test the vacuum cleaner:

  • Rice – 0.5 ounces
  • Dry Cereal – 0.5 ounce
  • Kitty Litter – 0.5 ounces
  • Sugar – 0.5 ounces

We use an engineered hardwood floor as our base test.  Low-pile and high-pile carpet inserts are laid over the hardwood floor to do the carpet testing. Debris is scattered over each type of floor covering one at a time.

We use the same vacuum cleaning process to test all our vacuum cleaners. This creates a true to life real world, consistent and fair atmosphere to provide the performance assessment.

Here is the procedure:

  1. Measure each type of testing debris by weight
  2. Create a debris field in the testing lane by spreading the respective debris type.
  3. Run the vacuum cleaner over the testing lane and debris.
  4. Run a high powered vacuum over the test lane to remove any debris left behind
  5. Empty and weigh any debris that we were able to remove in step 4

RELATED See our other robot vacuum reviews here.

Roborock S4 Cleaning Data

Here’s the data from our Roborock S4 cleaning tests.





Low Carpet


High Carpet


Hardwood Floor Cleaning

Unsurprisingly, hardwood floor cleaning performance was excellent. The Roborock S4 removed 99% of all debris in our hardwood floor cleaning tests.

Roborock S4 cleaning on hardwood floors

This is effectively the same as we saw on our Roborock S5 and S6 tests.

Debris left behind in the corners
Debris left behind in the corners

The only slight issue we saw was a few debris that got left in the corners. However, these debris were not significant enough to trigger a weight on our scale.

Low-Pile Carpet Cleaning

Our tests on low pile carpet were also quite good. The Roborock S4 removed 93% of all debris.

Roborock S4 low pile carpet cleaning tests

This is actually slightly better than what we saw on our Roborock S5 and S6 tests (which removed 91% and 85%, respectively).

In any case, a 93% is a solid score in its own right.

Roborock S4 cleaning on low carpets
Roborock S4 cleaning on low carpets

The only debris that got left behind was a fine mix of sugar and kitty litter.

High-Pile Carpet Cleaning

Our tests on high pile carpet were actually a bit confusing. Typically on robot vacuums we see the best results on hardwoods, with waning results on low pile carpet, and then the worst results on high pile carpet.

Roborock S4 high pile carpet cleaning tests

However, the S4 removed 97% of all debris on our high pile carpet test. This is significantly more than the Roborock S5 and S6.

While the S4 does have a few upgrades over the S5 and S6, it’s our understanding that raw suction power isn’t among them. As a result, we will probably look to re-do our S5 and S6 tests to ensure those robots (or our testing team) didn’t experience any sort of hiccups during our initial test.

Roborock S4 cleaning high pile carpets
Roborock S4 cleaning high pile carpets

In any case, a 97% is truly an exceptional score for a robot on high pile carpets.

More Roborock Reviews

You can find our complete list of Roborock reviews here:

Usability & Maneuverability

The controls on top of the Roborock S4 are simple, which makes it intuitive and easy to use. 

Using the robot vacuum with the Roborock app is beneficial, providing feedback on cleaning cycles and reports. Downloading the app is worthwhile to get the best user experience.

Roborock app scheduling & timer features
Scheduling and timer feature within the Roborock app

The added customizable features in the app gives it more usability value.

As far as maneuverability, the round S4 robot vacuum moves around smoothly. It’s capable of reversing it’s position to prevent getting stuck on an obstacle. The S4’s low profile also means it can fit under most furniture.

  • Weight: 7 pounds
  • Width: 13.8″
  • Height: 3.8″
  • Turning: 360°

RELATED – Want to see how full sized vacuums compare? See our best vacuum cleaner reviews here.

Roborock S4 Maintenance

Maintaining the S4 doesn’t take much effort. Within the app you can monitor various maintenance tasks.

Monitoring maintenance tasks within the app
Parts monitor within the Roborock app

Here are the tasks involved:

  1. Regularly empty the dust bin: This is the most common maintenance task. The dust bin should be emptied after each cleaning cycle.
  2. Wash dust bin and HEPA filter: Allow proper drying time, a minimum of 24 hours before placing back in the vacuum.
  3. Replace HEPA filters (as needed)
  4. Replace battery (as needed): Most robot vacuum batteries last 2-3 years thought this is just an estimate as the manufacturer does not give a lifespan on the included battery.
  5. Remove obstructions from brushroll: You’ll want to periodically remove the brushroll to remove hair and any other obstructions.
Removing Roborock S4 brushroll
Removing Roborock S4 brushroll

Is the Roborock S4 a good value?

With all the specs, features, and technology, is the Roborock S4 considered a good value?

It has a long run time, intuitive technology, and an accompanying app, which all add to the value. Unlike the S5 and S6 though, it only serves as a vacuum cleaner and doesn’t work as a mop.

Roborock S4 under the hood
The dust bin is accessed under the S4 hood

While it lacks the mop, the price is notably better and the new drive-train system is a great upgrade. One of the most common issues for robot vacuums (especially budget robots) is they get stuck.

Emptying roborock S4 dust bin
Emptying roborock S4 dust bin

Being able to back up seems like a small thing, but it makes a big impact on keeping the Roborock S4 vacuuming without you needing to periodically rescue it.

When you combine this alongside the excellent cleaning performance it’s a solid value overall.

Roborock S4 Specifications

SpecificationsRoborock S4
Weight8.0 lbs.
Floor TypeAll (indoor)
Battery5,200 mAh
Run Time150 mins
Cleaning Area~2,700 sq. ft.
Dust Bin Capacity480 mL
Includes Digital WallYes
ReturnsVaries by retailer, other retailers will vary
Warranty1-Year Limited
PriceCheck Price

Should you buy the Roborock S4?

As far as robot vacuum cleaners go, the S4 model has some nice features and technology packed into it. 

Wondering if the Roborock S4 is the right vacuum cleaner for you?

The Roborock S4 is best if you want:

  • Great cleaning performance: Cleaning performance was excellent overall. The S4 scored an average of 96% overall. Most notably was its ability to clean high pile carpets, where it scored a 97% (an area where robot vacuums tend to struggle). It’s every bit as good as any full sized vacuum cleaner (and better than many budget vacuums).
  • Tech savvy options: The Roborock app creates a hands off approach to using the Roborock S4. Naming rooms, creating virtual barriers and “No-Go Zones,” getting cleaning reports, and being able to view cleaning cycle patterns are just a few of the options. For tech lovers, the S4 might be a good option.
  • Long battery life:  The battery in the S4 model is a 5,200 mAH lithium ion powerhouse. It can last up to 150 minutes (2.5 hours) on one charge. Once the charge reaches a certain point, the S4 will head back to the charging station, recharge, and then get right back to where it left off.
  • Intuitive navigation: The Roborock S4 offers several different ways to optimize its on-board navigation system. It uses a Z-shape cleaning pattern so it doesn’t miss a spot  and digitally maps and remembers rooms. The S4 also includes self-adjusting brush heads and suction to move from one floor type to the next with ease and without slowing down.

For more information on the Roborock S4 robot vacuum see here.


  • December 1, 2020 – Roborock informed us that the S4 is being discontinued. We added an update alert to the top of the page.
  • September 23, 2019 – Initial version of the page was published.
Roborock Does It Again
  • Design - 97%
  • Performance - 96%
  • Quality - 94%
  • Usability - 97%
  • Value - 95%


The Roborock S4 is the newest robot from Roborock. It’s designed to be slightly simpler than the S5 and S6, dropping the mopping attachment. However, it adds an all new drive train that can go both forwards and backwards, allowing it to escape situations that might have resulting it in getting stuck without it. Cleaning performance was solid, as was navigation. The biggest upgrade is the new Roborock app, which the S4 and S6 are both compatible with. The app is fully featured, including digital maps, reports, no go zones, virtual walls, schedules, cleaning modes, and more. Excellent value and another great build from Roborock.

About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of He has been featured in Fast Company, Reader's Digest, Business Insider,, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

Need Help? Ask Your Question Below.

30 Comments on “Roborock S4 Review”

  1. I just purchased the S4 and it is to be delivered the 1st of February nowhere did I see that this was discontinued until I happened to be on your site.
    The one I order is not an S4 Max it says S4.
    So what does it mean since I’m gettimg the S4 do you think is is a used one it did not specify that.
    Since they are not making it anymore how do I get parts,
    I am really confused since I found this information out and don’t know what’s going to happen if I can’t get parts for it.
    Wouldn’t you have thought they would have informed me when I order it that it was discontinued.
    Pls advise

    Dec 23 2020

    • There is no reason to think it’s used. Retailers typically have a large stock of products, so even if an item is discontinued they may continue to sell it until their stock is gone.

      I don’t think there is any risk of parts not being available. Roborock’s robots use many interchangeable parts, so the stuff that works on the S4 Max should also work on the S4.

      If you’re still worried, I’d just return the S4 and order an S4 Max.

  2. Thank you for your very thorough and helpful review of the Roborock S4.
    I have read so many reviews on vac robots. I have also been trying to find where I can buy this vac, even and have them as not being available or if they will be. Could this company based in China be affected by COVID or other reasons not be making them now or again?

    Please help me find out, as I am convinced that I prefer Roborock over Roomba.

    With much appreciation for your help,

    • I’m not sure what’s going on with it. I’ve seen it come in and out a few times now.

      Doesn’t seem to be discontinued, but they do seem to have stocking issues (probably due to demand).

      See here for S4 –

    • I’ve checked Amazon over the past week, they don’t seem to know. Sure hope Roborock gets back on the market. Right now I don’t see another choice like the S4 – price wise with the laser navigation. Also concerned about buying a product that might not be serviced after.
      Thanks for your help.


    • I reached out to my Roborock contact today.

      Roborock S4 and S5 are being discontinued.

      Roborock S4 Max and S5 Max / S6 Pure will be their logical replacements in performance / price.

      I’ll update our S4 and S5 reviews later this week.

    • Thank you so much, Derek. Did your rep say when the S4Max will be back on the market, because I started looking at it then couldn’t find it either. Ended up with your site and figured that the S4 was a good alternative. I don’t want a mop feature on it. Just more to pay for and I’ve read that the mopping feature isn’t the best on these little guys.

      I’m impressed that you reply to my inquiries – in Canada, as you and your team are in US and way out in cyber space. I read the bio about your company. SO neat, a family group, and how in-depth your research and evaluations are. This is a valuable service to people who need to sort out the details or sometimes lack of. Continue your great work.


    • He did not. I imagine they are out of stock due to Black Friday / Cyber Monday. Typically it takes them a couple of week to get more stock in after a big purchase spree like this.

      Thank you very much for your kind words. We’re very blessed to get to do what we do for work. I’m glad to hear we were able to help and I hope it won’t be the last time! 🙂

  3. I think the issue regarding how well the S4 works on high pile carpets is down to how some people might describe carpets as high-pile others would describe them as medium pile. I would say your high-pile carpet is more like a medium pile. We have low and medium pile carpets and it handles them well, but the S4 cannot handle our rug which is what I would call high-pile.

    • I suppose there is a degree of subjectivity. But I can tell you, these were not our assessments.

      To acquire our carpet samples we went to a local carpet shop and asked to purchase a “typical low and and high pile carpet”.

      As there is no absolute length / thickness that determines carpet pile there is always going to be some level of variance.

  4. Thanks for your review. Can you tell me what is the actual measured size of the S4’s dust bin? The Roborock site indicates 420ml… which is very small. I have seen some reviews and pictures which suggest it is much larger. And looks to be as large as the E25 and E35 dust bins which are 640ml. What is your experience in use and did you measure its actual size? I hope its not really 420ml. Looks like a very capable vac but 420ml would be limiting.

    • S4 dust bin is 8.5″ x 3.5″ x 2.5″

      I checked the S6 dust bin, and it’s about the same size.

      To clarify, the E35 and E25 do have the larger dust bins. The S-series redesigned the entire robot, so the bin sits different within the machine.

      In my experience the smaller dust bin really wasn’t a big detractor. Sure, bigger is better, but it still has enough capacity that you can let it run for 2-3 cycles (at least in our home) before needing to empty.

  5. Hi,

    Looking at buying the S4 but just have a couple of questions.

    How does it handle going from floor onto rugs? Can it handle this? As we have a rug in the middle of the main room we would use it in and it would need to be able to handle the change well.

    Also, is it good for laminate flooring. I only ask because with the spinning brush underneath i’m worried it might scratch the flooring.

    • In most cases it will handle rugs perfectly fine. If it’s a really tall rug and/or has a shag pile, then that may cause issues. Otherwise you should be fine.

      As with laminate, in most cases it’s going to be good. Cleaning performance on laminate will be nearly identical to what it’s capable of doing on hardwood floors. If you’re worried about scratching you should contact your laminate floor manufacturer to see what they recommend.

      That said, I have never heard of a case where a robot vacuum scratched a laminate floor.

  6. How do I manually set up barriers without using the app? Would a strip of black tape around an area stop my roborock from cleaning that area?

    • You cannot. You have to use the app to setup barriers.

      Otherwise you would have to physically block off the space (es. physically closing the door). A strip of black tape will not stop it.

  7. This info you provide is incorrect, the S4 only has 2 buttons on the machine. “Here is how the buttons are used to control the robot vacuum:

    Power on / off (long press the middle button to activate)
    Start / pause the current cleaning cycle (short press the middle button to start or pause)
    Spot clean (button to the left of power button)
    Send to charger (button to the right of power button)”
    Hope you take the time to edit your review.

  8. Just ordered one of these. I hope it works well as I will not spend the extra for an S6 model as I don’t need the mopping feature. Thanks for the review.

    • You’re very welcome! I’m happy to hear you found it helpful.

      I don’t think you’ll be disappointed.

  9. I am very confused with your review of the roborock s4. Amazon and xiaomi among others say it only works on non carpet or low to medium pile carpet. There a lot of errors on carpet according to consumers. YOU say that it even works better on high pile carpet. What’s the deal who is right.

    • Hey Bill,

      We think it works well on high pile carpets because we tested it on high pile carpets and it worked well. It’s as simple as that.

      When it comes to our performance tests we don’t take anything for granted, which is why we test in our testing lab against real debris on 3 different floors. Then we publish our findings.

      I am surprised to hear that other consumers are complaining about the carpets. However, we experienced no issues during our tests.

      One last clarifying note – Xiaomi is not Roborock. The Roborock S4 is a standalone robot built and design by Roborock. While it does work with Xiaomi Mi app and I believe might be sold on some of their websites these are two separate companies. As such, I would trust information directly from Roborock more than Xioami.

  10. This is a little misleading I think… I’ve borrowed a friend’s S6 and the app has an additional tab called “Room” which is where you can specify rooms. Zones is *not* the same thing. Zones allows you to draw a boxed “zone” for cleaning. On the S6, once the robot has done a full pass of the house, it will automatically divide it into separate coloured rooms.

    As far as I can tell (and I am hoping you can confirm), this is not the case with the S4.

    • You should double check to make sure you have downloaded the Roborock app and not the Xiaomi Mi (or any other app that the Roborock will sync to). The newer Roborock app has more features and does have zoned cleaning (not just room cleaning).

      I was curious about your comment so I just double checked.

      Click enter robot > click “Zone” (bottom of the screen, right above the clean button). There you can create little zoned cleaning boxes exactly as you have described above. Roborock S4, S5, S5 Max, and S6 all use the same zone cleaning via the app.

  11. thx for the info!
    I Already bought one and i’m impressed by the cleaning performance.
    Just one more question.

    How do I split my map into several rooms?

    • Hey Oliver,

      I sent a message to Roborock last week with your question, but I’ve yet to hear back.

      In any case, based on my own understanding and use of the app I have not seen any way to access multiple floors on the S4. If I find out different in the future I’ll let you know.