Contributing author: Jennifer Blair
Comparing the Roomba i4 and the Roomba i8
Comparing the Roomba i4 EVO with the Roomba i8+ pits a midrange robot vacuum against a high-end model. Both models share a lot of features, but there are several key differences, too. Which comes out on top: the one with the most features or the one that’s most affordable?
The BestReviews Testing Lab put both the Roomba i4 EVO and i8+ through their paces, noting navigation, carpet performance, hardwood performance, suction and more. We think the Roomba i8+ may top the i4 EVO when it comes to navigation and features, but its high price tips the balance to the better-performing Roomba i4 EVO.
Roomba i4 EVO and i8+ specs
As models from the consumer-focused Roomba i series, the Roomba i4 EVO and i8+ share similar dimensions, batteries, dustbins and other capabilities.
Roomba i4 EVO specs
Battery life: 94 minutes | Dimensions: 13.34” L x 13.26” W x 3.63” H | Dustbin capacity: 0.5 L | Weight: 7.44 lb | Navigation software: iAdapt 3.0 | Mapping: Yes| Self-emptying: No | Object avoidance: No | Scheduling: Yes | Selective room cleaning: Yes | Warranty: 1 year limited
The Roomba i4 EVO was introduced in 2021 and was upgraded to include smart mapping the following year, which is when it became the i4 EVO. It features a 90- to 100-minute battery life, with a rounded shape slightly narrower, taller and heavier than older Roombas. It runs iRobot’s iAdapt 3.0 navigation software, which supports mapping and row-by-row cleaning, but it lacks active object avoidance or target-area cleaning. While compatible with self-emptying bins, the Roomba i4 EVO isn’t sold with one.
Roomba i8+ specs
Battery life: 89 minutes | Dimensions: 13.26” L x 13.26” W x 3.63” H | Dustbin capacity: 0.5 L | Weight: 7.44 lb | Navigation software: iAdapt 3.0 w/ VSLAM | Mapping: Yes | Self-emptying: Yes | Object avoidance: Yes | Scheduling: Yes | Selective room cleaning: Yes | Warranty: 1 year limited
The Roomba i8+ was introduced in 2019. It has the same battery as the Roomba i4, with the same overall dimensions and weight and the same size dirt bin. The Roomba i8+ runs on iAdapt 3.0 navigation software but with VSLAM (visual simultaneous localization and mapping) technology. It supports mapping, row-by-row cleaning, object avoidance, and targeted room or area cleaning. A self-emptying model, it comes with the Clean Base Automatic Dirt Disposal and charging dock, which can hold up to 60 days’ worth of debris.
A major difference between the Roomba i4 EVO and i8+ is the presence of a camera on the i8+. This camera allows the i8+ to navigate visually rather than by distance and position alone like the i4 EVO. However, vSLAM navigation needs light to operate, so the i8+ can’t navigate in the dark like the i4 EVO can.
More cliff sensors
Roombas use their cliff sensors, located on their underside, to detect stairs and avoid falls. The Roomba i4 EVO has four cliff sensors, two in the front and two by the main wheels, while the i8+ has six, with two more behind the wheels.
Self-emptying bin and dock
The Roomba i8+ comes with a self-emptying dustbin and Clean Base Automatic Dirt Disposal dock that removes and stores dirt for up to 60 days before needing to be emptied. The Roomba i4 EVO is compatible with the same bin and dock, but they have to be purchased separately.
Both the Roomba i4 EVO and i8+ use rubber rollers instead of a bristle brush to lift and remove dirt. However, the Roomba i8+ only has one multisurface roller, paired instead with a beater roller found on older Roombas. The i4 EVO has a pair of multisurface rollers, giving it a cleaning edge.
Cleans specific areas
While the Roomba i4 EVO supports mapping and can be sent to clean a specific room, it can’t define areas within a room, such as “under the kitchen table” or “in front of the couch.” The Roomba i8+, on the other hand, supports target areas and can be sent to clean them directly.
Setup was straightforward for both the Roomba i4 EVO and i8 in our testing. Both robots came fully assembled. We placed their docks where the robots could roll on and off easily, and plugged them into AC outlets. We let the test models charge fully while we set up the iRobot Home app.
App setup took only a couple of minutes for the i8+. Roomba i4 EVO setup should have been easy as well, except the instructions referred to a QR code we couldn’t find, so we had to choose and pair the i4 manually. Once this was done, connecting either robot to Wi-Fi took less than 15 seconds. The app guided us step by step.
Both the Roomba i4 EVO and i8+ have the same level of suction, which iRobot describes as 10 times that of the entry-level 600-series Roombas. However, we found that the Roomba i4 EVO did better than the i8+ on carpet, with high scores in all our tests.
The Roomba i4 EVO removed all visible traces of ground coffee from medium-pile carpet, while the i8+ left a few grains of kosher salt behind. Both models crushed pieces in our breakfast cereal test, but the i4 EVO picked up all of the crumbs, while the i8+ left some behind. Both did well with pet hair, leaving no trace, but both were average when it came to corners, leaving about a fourth of the test material behind.
The Roomba i8 inched out the i4 EVO on hardwood, matching it in table-salt tests but suffering from the same problems in the breakfast-cereal test, in that both models’ side brushes scattered cereal far and wide beyond the robots’ reach. The Roomba i8+ removed most of the table salt we spilled in a corner, while the i4 EVO left a visible amount behind. Both models removed all the pet litter we placed on bare flooring.
Both models are quieter than full-sized vacuums, with the i4 EVO registering between 55 to 63 decibels. However, the i8+’s Clean Base can briefly get as loud as a full-sized vacuum when emptying the i8+’s dustbin.
The Roomba i8+ has a glossy finish on top in light gray, with a large black cutout containing the control buttons and the recess for the vSLAM camera. The i4 EVO has a subtler design, with fabric-textured plastic on its top plate around a metal-textured center area for the control buttons, all in dark gray.
The Clean Base that comes with the i8+ stands almost 20 inches tall, which is hard to miss and not so easy to hide out of sight.
The Roomba i4 EVO supports mapping, as does the Roomba i8+. Both clean in orderly, overlapping rows whenever they can, allowing them to cover most of the floor area of a room. The i4 EVO uses its odometer and gyroscope to orient itself and find landmarks like walls and furniture to compare to its map. As we noted, however, the Roomba i8+ uses its camera to steer visually, making it navigate faster and more directly.
The Roomba i8+ took only 12 minutes to map 250 square feet, compared to 43 minutes for 366 square feet for the i4 EVO, more than twice as long. We sent the i8+ to a specific area under a kitchen table on a cleaning job, and it obeyed exactly, which we couldn’t attempt with the i4 EVO. The i4 EVO navigated well based on its map, but ran into things it didn’t expect, like toys, pens and even the feet of testers. However, the i8+, even with its camera, doesn’t have the kind of active object avoidance that would allow it to avoid pet waste.
The Roomba i8+’s self-emptying feature impressed us during testing. The i8+ automatically proceeds to its Clean Base dock after finishing a job, and the dock activates the suction that empties the contents of the i8+ dustbin. We checked the test model’s dustbin afterward and found almost nothing left inside. Since the i4 EVO doesn’t come with a Clean Base dock, its dustbin has to be emptied by hand. It can, however, let the user know if the bin is full.
Both the Roomba i4 EVO and i8+ have a dirt-detection feature that slows them down and increases suction when they find concentrated dirt on the floor. The self-adjusting wheels and tangle-avoidance smarts of both models let them negotiate floor transitions well, although the i8+ tried to go under a rug on hardwood at first before going over it, which the i4 EVO did not do.
Both models use HEPA-type high-performance filters in their dustbins, to capture particulates down to 0.5 microns, making them good choices for allergy sufferers. Both models support virtual barrier technology, preventing them from entering specific rooms or semicircular areas, although the latter did not work particularly well while testing the i8+.
Both the Roomba i4 EVO and i8+ support spot-cleaning, letting you place them on top of dirt and have them spiral outward and inward until the dirt is gone. Both models can be controlled remotely by the iRobot Home app, including scheduling, and be controlled via Alexa, Google Home and, in a more limited way, Siri.
The Roomba i4 EVO with dock, extra filters and virtual barrier module costs $399.99 directly from iRobot, pricier than comparable midrange competitors. The Roomba i8+ with Clean Base, extra dust bags, filters and virtual barrier costs $899.99. It was originally a Costco exclusive, but can now also be found on Best Buy. At this price, it costs more than the newer Roomba j7+, that also has self-emptying capabilities plus active object avoidance.
Both the Roomba i4 EVO and i8+ use the same rechargeable, user-replaceable 2,210 mAH (milliampere hour) lithium-ion battery, with a suggested battery life of 90 minutes per charge. Our tests agreed with this: The Roomba i4 EVO lasted 94 minutes before needing to recharge, and the Roomba i8+ lasting 89 minutes. Our i4 EVO test model took almost two hours to fully recharge compared to 102 minutes for the i8+.
The Roomba i8+ beats the Roomba i4 EVO on features, but its high cost, especially compared to newer models, and lackluster performance on carpet make its superiority somewhat questionable. The Roomba i4 EVO does less, but does all the important things well. For the money, the Roomba i4 EVO is a better choice than the i8+.
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Jmar Gambol writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
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