The Roborock S4 is a mid-range robot vacuum in Roborock's vacuum lineup with outstanding performance on bare floors. It effectively cleans hair on bare floors and on low-pile carpet so it's an ideal choice if you have a pet and your house has those surfaces. Unfortunately, it doesn't work on high-pile carpet as once it gets on, it doesn't clean anything and notifies you to move it to another location. Its smart pathing feature is effective at cleaning a room as it learns a new path every time it cleans, so it's efficient at moving around objects. It's a bit difficult to maintain and you also need to buy replacement parts regularly. On the upside, it has an excellent battery life and the dirt compartment is of good size for a robot vacuum.
Great for use on bare floors. The Roborock S4 has outstanding performance on bare floors as it sucks up almost all debris of any kind. Its smart pathing feature is effective at cleaning a room and it has a good-sized dirt compartment for a robot vacuum. Unfortunately, it's a bit difficult to maintain and there are a few recurring costs associated with the vacuum.
The Roborock S4 isn't bad for low-pile carpet. It cleans most hair and large debris on low-pile carpet but struggles a bit with small debris. It has great maneuverability and its dirt compartment is a good size for a robot vacuum. Sadly, you're going to need to clean quite a few parts regularly and buy replacements for them too.
The Roborock S4 doesn't work on high-pile carpet. It has trouble getting on, doesn't clean anything, and then asks to be moved to another location.
The Roborock S4 is a decent vacuum to clean pet hair. It does an impressive job at sucking up hair on both bare floors and low-pile carpet but it doesn't work on high-pile carpet. You can also remove the brushroll if hair gets tangled and it has a dedicated brushroll cleaning tool with a hook to help remove hair.
The Roborock S4 isn't designed to be used on stairs.
The Roborock S4 isn't designed to be used in cars.
The S4 has a great build quality. It's made out of a hard plastic that has a glossy finish on top, which is transparent so you can see if the dirt compartment is full. The dirt compartment is plastic but could break if dropped on the floor. The two main wheels are made out of durable rubber and the laser distance sensor on top has a matte plastic finish like the bumper of the vacuum. Also, there are two wide charging contact slots on the vacuum, making it easier to dock and charge.
There's virtually no assembly required. All you have to do is connect the vacuum to your mobile device with either the Mi Home or Roborock apps and set up the vacuum with the charging station.
The S4 is a bit difficult to maintain as there are a lot of parts that you need to clean. Luckily, each part is easy to take off.
The Mi Home app lets you know which parts need to be replaced based on total hours used. This is only for when you need to buy a new part and not clean a specific piece.
Unfortunately, the S4 robot vacuum has a few recurring costs. The app has a 'Maintenance' tab that indicates the total hours left for each accessory that needs changing. Roborock recommends changing the filter every four to five months, the side brush every three to six months, and the main brushroll every 6-12 months, as long as each part is cleaned regularly. Each part is sold on Roborock's store on Amazon.
The S4 has excellent storing capability. This vacuum mounts to the charging station on its own, and you can hide the cables behind the station with a cord management cover.
The dirt compartment is decently-sized and a good size for a robot vacuum. Still, it needs frequent emptying and the app notifies you when it's full. If you want a similarly-performing robot vacuum with a bigger dirt compartment, consider the Roborock E4.
The S4 has an unlimited range as long as it still has a battery, but it isn't able to go up stairs.
Good portability. The S4 is small but may be heavy to carry around for some people if you need to bring it to another floor.
The S4 has excellent battery life. On its 'Max' mode, which is the most powerful, it lasts almost two hours, and on the least powerful mode, 'Silent', it lasts well over three hours. It takes three hours to charge, but it has a much better life-to-charging ratio than the Samsung POWERbot R7040. The Power button on the vacuum is red when there's less than 20% battery life left; otherwise, the button is white. You can also see the battery percentage on the app.
The S4 robot vacuum has a few extra features. It has four different suction modes, 'Silent,' 'Balanced,' 'Turbo,' and 'Max' that changes the power of the suction. It also has an automatic surface type adjustment that changes the speed of the brushroll depending on the surface. Near walls, it spins faster to pick up as much debris as possible, while in the middle of a room it's slower so that debris doesn't go flying. This vacuum also has built-in speakers, notifying you of its status or whether cleaning is complete, if the dust bin is full, etc.
The S4 has a main brushroll and a side brush that picks up debris in blind spots and carries debris under the vacuum so that it's picked up. Also, there's a small brush to clean the main brushroll.
The S4 has an outstanding performance on bare floors. It has no trouble cleaning small debris like rice and it sucks up most pet hair and large debris like Cheerios. It picks up most large debris, but large debris could get stuck under the vacuum and get dragged to the dock. You may have to manually clean around the charging dock if the vacuum is cleaning large debris like cereal.
The S4 isn't bad on low-pile carpet. The vacuum struggles cleaning small debris like baking soda but still does an excellent job cleaning hair. With large debris, it quickly loses performance as the dirt compartment fills up.
Unlike the Roborock S5 or the Roborock S6, this robot vacuum can't be used on high-pile carpet. It has a hard time getting onto the carpet and once on, it says it's done cleaning, even though it doesn't really move. It loses its sense of direction on high-pile carpet and asks to be moved to another location.
Great maneuverability. The laser sensor navigation is effective and the robot vacuum uses smart pathing technology. It learns a new path after each cleaning session, making it more efficient around objects, and you can also set barriers around smaller objects like cables. It's small enough to fit under couches and tables, but when it gets stuck on a rug, it stops itself.
The S4 has excellent automation features. There are two apps available, the Mi Home and Roborock apps, which have the same layout and features, but Mi Home is compatible with other smart devices. Through the app, you can schedule cleaning times, set boundaries, designate cleaning in a specific room, and see when different parts need maintenance. The vacuum also returns to the charging station on its own, even if you move the dock because of its advanced mapping technology.
You can also use the buttons to control the vacuum without an Internet connection. Pressing the Power button enables a full house clean, holding the Home button for 3 seconds enables a spot clean, and pressing the Home button sends it to the dock.
The Roborock S4 is good robot vacuum that's ideal for use on bare floors. If you have high-pile carpet, there are better robot vacuums, such as the Roborock S5. Also see our recommendations for the best robot vacuums for pet hair, best vacuums, and best robot vacuums.
The Roborock E4 is a better overall robot vacuum than the Roborock S4. The E4 delivers stronger performance on all surface types, especially high-pile carpet, and has a slightly larger dirt compartment. However, the S4 has a shorter recharge time as well as a LIDAR navigation system that creates a more efficient cleaning path. You can also set up virtual boundary markers in its companion app.
The Roborock S6 is a better robot vacuum than the Roborock S4. The S6 cleans all surface types much better, especially because it can climb onto high-pile carpet, and it has a mopping feature, although we don't currently test for this. It also has slightly better maneuverability, and build quality. That being said, the battery life of both vacuums is very similar, so if you don't have carpet in your home, the S4 could be a good alternative.
The Roborock S5 is a bit better overall than the Roborock S4. They both have similar performance on bare floors and low-pile carpet but the main difference is that the S5 is able to clean high-pile carpet while the S4 can't. Besides that, they each require the same maintenance needs, have the same dirt compartment, and the batteries are similar.
The Roborock S4 is much better than the iRobot Roomba 675. The Roborock has much better performance on bare floors and low-pile carpet, but it can't clean on high-pile carpet, while the iRobot can clean some hair on high-pile carpet. The Roborock also has better automation features and a bigger dirt compartment. The battery on the iRobot takes less time to charge.
The Roborock S4 is much better than the eufy RoboVac 30C. It performs much better on bare floors and low-pile carpet but it doesn't work on high-pile carpet. Instead, the eufy works on high-pile carpet but it doesn't clean much on it. The Roborock also has more automation features, a better build quality, and a better battery.
The Roborock S4 is a bit better overall vacuum than the iRobot Roomba E5. The Roborock easily cleans any type of debris on bare floors but it starts to struggles on low-pile carpet, and it doesn't work at all on high-pile carpet. The iRobot is better to use on carpet because of this. The Roborock has a bigger dirt compartment, a much longer battery life, and there are a bit less recurring costs.
The Roborock S4 is a better vacuum for use on bare floors while the Samsung POWERbot R7040 is a bit better on carpet, although it's still not good on that surface. The Roborock cleans up almost all debris on bare floors, it has a much better battery, the dirt compartment is bigger, and it has a better build quality. However, the Samsung is easier to maintain and there are no recurring costs.
The Roborock S4 and the Shark AI Robot have different strengths and depending on your preferences, you may prefer one over the other. The Roborock is better-built, easier to maintain, and has a significantly better performance on bare floors. However, the Shark can climb onto high-pile carpet to clean it, though it still has sub-par performance on this surface type.