Contributing author: Jennifer Blair
iRobot’s Roomba i3+ EVO and Roomba i4+ EVO are mid-priced robot vacuums that seem, at first glance, to be almost identical. Belonging to the eighth generation of iRobot’s Roomba line overall, the Roomba i3+ EVO and Roomba i4+ EVO look alike, sound alike and share similar specs and accessories.
Compared to the Roomba i3+ EVO, the i4+ EVO’s main differences on paper are its 20% larger battery and slightly different color on the face plate. While both models come with the i-series Clean Base Automatic Dirt Disposal dock to empty their dustbins into, if you don’t feel the need for the self-emptying feature, you can get the i4 EVO by itself for less.
With so much the same, it would seem that there should be no significant difference between these two Roombas. To our surprise, however, when we evaluated both in the BestReviews Testing Lab, the Roomba i4+ EVO emerged as the clearly superior performer, cleaning better, more thoroughly and with fewer frustrations compared to the i3+ EVO.
Both the Roomba i3+ EVO and the Roomba i4+ EVO share many specs in common. Their chief difference, spec-wise, is that the Roomba i4+ EVO has a larger battery, for a longer run time and marginally faster charging. Both models share the same design language with a textured top surface for a somewhat more premium look than base Roomba models.
Product specifications
Battery life: 96 minutes | Dimensions: 13.26” L x 13.26” W x 3.63” H | Dustbin capacity: 0.5 L | Weight: 7.44 lb | Mapping: Yes | Self-emptying: Yes | Object avoidance: No | Scheduling: Yes
The Roomba i3 and i3+ (the plus sign indicates that it comes with the Clean Base Automatic Dirt Disposal dock) were first introduced in 2020. But two years later, the Roomba i3+ added EVO to its name when it was upgraded to support iRobot’s iAdapt 3.0 navigation technology, giving it smart-mapping capabilities for the first time.
Powered by an 1,800 mAH (milliampere-hours) lithium-ion battery that iRobot claims lasts 87 minutes on a full charge, it ran for a full 96 minutes in one room during our testing. This battery size and capacity is something the Roomba i3+ EVO shares with the base-model Roomba 600 series. However, if it does run low on power in the middle of a job, it will return to its dock, recharge itself and pick up cleaning where it left off.
Compared to the Roomba 600 models, the Roomba i3+ EVO is slightly heavier at 7.44 pounds, giving it a sturdier, higher-quality feel. It’s also a bit taller, which allows it to completely avoid some spaces the shorter Roombas try to enter; this height does prevent it from slipping under low furniture the way low-profile competitors can. Its dustbin holds half a liter of dirt, which it empties automatically into its Clean Base station.
Read more: iRobot Roomba i3+ EVO
Product specifications
Battery life: 92 minutes | Dimensions: 13.34” L x 13.26” W x 3.63” H | Dustbin capacity: 0.5 L | Weight: 7.44 lb | Mapping: Yes | Self-emptying: No | Object avoidance: No | Scheduling: Yes
Released in 2021 as Costco exclusives but now sold elsewhere, the Roomba i4 and i4+ gained smart-mapping technology and the EVO name in 2022, just like the i3 and i3+. The Roomba i4+ EVO features a larger 2,210 mAH lithium-ion battery than the Roomba i3+ EVO for a stated longer run time of 100 minutes. In our testing, however, the Roomba i4+ EVO’s battery actually lasted only 92 minutes, slightly less than the Roomba i3+ EVO, a result that might be attributed to a heavier test workload, including a mapping run and a whole-apartment cleaning run rather than just one room. But because it has the same automatic recharging feature as the i3+ EVO, battery life isn’t as important.
The Roomba i4+ EVO is almost identical to the Roomba i3+ EVO in dimensions and weight. Like the Roomba i3+ EVO, the Roomba i4+ EVO has an internal dustbin with a capacity of half a liter, enough for everyday light cleaning and emptying every now and then. With the iRobot Home app, the Roomba i4+ EVO can be set to refuse to start if its dustbin is full, a good way to know when you need to empty it. The Roomba i4+ EVO supports smart mapping and scheduling.
Read more: iRobot Roomba i4+ EVO
The Roomba i3+ EVO and the Roomba i4+ EVO are marketed by iRobot as having the same suction power. iRobot doesn’t publish suction power values, but the company says both models have 10 times the suction of the base Roomba 600 series.
In our testing, however, we found a noticeable difference in suction performance between the two models. We rated the Roomba i3 EVO only slightly above average in our carpet tests, leaving a wad of pet hair behind and crushing cereal into the fibers. On the other hand, we thought the Roomba i4+ EVO performed impressively, leaving less residue and tracking down debris its first passes may have scattered. Like the Roomba i3+ EVO, the Roomba i4+ EVO crushed some cereal into the carpet pile on a cleaning job, but it removed the debris completely. Neither model fared particularly well in corner tests on carpet or hard flooring such as laminate, tile and vinyl plank, leaving both small and large debris behind in our tests.
Both the Roomba i3+ EVO and the Roomba i4+ EVO have rubber multisurface rollers instead of bristle brush rollers. The rubber rollers resist getting tangled in long hair, pet hair or string and are easier to clean than bristle rollers. A robot vacuum’s rollers matter almost as much to its cleaning performance as its suction, since the rollers pick up and move dirt to the suction area.
As for noise, both the Roomba i3+ EVO and the Roomba i4+ EVO have comparable noise levels of around 55 to 65 decibels. Both are significantly quieter than an upright or handheld vacuum. The Clean Base, which both models share, is about as loud as a standard vacuum, but only runs for a few seconds.
Setup for the Roomba i3+ EVO and the Roomba i4+ EVO was the same. Both models arrive fully assembled and are ready to charge on their docks. To set up their Wi-Fi connections, you need to download the iRobot Home app for your smartphone. iRobot provides a QR code on their quick-start cards to automate this process, but our test models lacked those codes. However, manually downloading and selecting them was no trouble at all.
We ran into trouble getting the i3+ EVO to charge fully out of the box. This required a reboot and restore of the unit, which was easy enough using the app. It could also be done via a button combination on the unit itself.
The Roomba i3+ EVO and Roomba i4+ EVO both support smart mapping. They learn and remember the layout of your home and store that map via the iRobot Home app for future reference. Once they have created a map, they can be sent to specific rooms; although, unlike more advanced Roombas, they can’t be sent automatically to specific areas within a room. Both the Roomba i3+ EVO and the Roomba i4+ EVO support Alexa and Google Assistant for voice commands and, unlike many competitors, can also work with Apple’s Siri assistant, although in a more limited fashion.
Unlike older or more basic robot vacuums, such as the Roomba 600 series, the Roomba i3+ EVO and Roomba i4+ EVO clean in systematic, orderly rows. This allows them to cover more area per room than more basic robot vacuums and clean rooms more efficiently.
We found that the Roomba i4+ EVO is noticeably better at finding its way around a room than the Roomba i3+ EVO. While neither has an obstacle-avoidance feature to help guide it around unexpected items in its path, the Roomba i4+ EVO seemed to sense and route around known obstacles better than did the Roomba i3+ EVO. Neither model uses a camera to get its bearings, instead using floor sensors and straight walls to orient themselves. This lets them operate in dim light and darkness as opposed to models with camera-based navigation.
While both models can recognize and avoid virtual barriers, only the Roomba i4+ EVO has the Dual Mode Virtual Wall Barrier included in its box. This small device, which emits an invisible barrier, can be placed anywhere you want to prevent a compatible robot vacuum from entering to protect items like pet bowls or delicate objects. While it’s nice to have, our experience indicates that you may be just as well served by simply closing a door or setting up a physical barrier.
Both models handled themselves well in surface transitions, including carpet to hardwood, hardwood to rug, and rug to hardwood, with occasional difficulty finding their way onto and climbing up thick pile.
Both the Roomba i3+ EVO and the Roomba i4+ EVO come with an i-series Clean Base self-emptying dock, which is especially handy for larger homes or homes with pets, so you don’t need to worry about emptying the robot’s internal dustbin yourself each day. This allows them to discharge any dirt they’ve collected into the large-capacity bagged bin of the Clean Base. Measuring 12.2 inches wide by 15.1 inches deep and 19 inches tall, the i-series Clean Base has a capacity of 57 liters, which iRobot says is enough for 60 days’ worth of debris.
While we could not verify this length of time during our testing period, we think it reasonable considering that a 30-minute cleaning job filled the i3+ EVO’s half-liter built-in dustbin. If you run a full two-hour cleaning job every day, that would come up to two liters a day, or only a 28.5-day capacity in the Clean Base. However, it’s not likely you’d come up with that much dirt in daily cleaning.
The Roomba i4+ EVO costs $649.99 on Amazon, while the Roomba i3+ EVO retails for $549.99 on iRobot. The i4 EVO without a Clean Base retails for $399.99 (as the Roomba i4) and is sold on Amazon and iRobot. The Roomba i4 models come with two extra high-performance filters and a virtual wall module, while the Roomba i3+ EVO comes with only one extra filter and no virtual wall module. Both the Roomba i3+ EVO and Roomba i4+ EVO are often available with regular discounts on various retailers.
For a pair of robot vacuums that are so similar, the differences in performance and user experience during our tests were surprising. The Roomba i4+ EVO beat out its almost-twin the Roomba i3+ EVO in nearly every category. When it comes to a face-off between mid-range Roombas with smart-navigation capabilities, the Roomba i4+ EVO wins over the Roomba i3+ EVO.
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Jmar Gambol writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
