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Roomba j7+ vs i7+ vs S9+ Comparison

Derek Hales

Written By: Derek Hales

Updated on:

For top-of-the-line vacuum performance, you may want to consider some of these best-performing Roombas.

This review comparison is going to look at the newer Roomba j7+ vs Roomba S9+ vs Roomba i7+.

Let’s dive in and see what’s new and different!

Roomba j7+
Roomba j7+
  • Cleaning: 99%
  • Run Time: 75 mins.
  • Run & Recharge: Yes
  • Smart Maps: Great
  • Base Capacity: 60 days
Roomba I Robot Vacuum Product Small
Roomba i7+
  • Cleaning: 99%
  • Run Time: 75 mins.
  • Run & Recharge: Yes
  • Smart Maps: Great
  • Base Capacity: 30 days
Roomba S Robot Vacuum Overall
Roomba S9+
  • Cleaning: 99%
  • Run Time: 75 mins.
  • Run & Recharge: Yes
  • Smart Maps: Great
  • Base Capacity: 30 days

Prefer to watch rather than read? We’ve got our complete Roomba j7+ vs. S9+ vs. i7+ video comparison below:

YouTube video

The Design

The design of each of these Roombas is each very similar. They are all considered to be top-tier Roombas with the most advanced features, navigation, and cleaning performance.

The main parts that make up the design of each Roomba includes:

  • The Shape
  • The Underside
  • The Controls
  • The Brushroll

The Shape

Both the Roomba j7+ and the i7+ are both round robot vacuums. In contrast, the Roomba S9+ is a D-shaped vacuum.

Round vacuums have the ability to make slightly tighter turns, while the D-shaped vacuum generally does a better job at cleaning into corners and along edges.

Roomba j7

Roomba j7+ robot vacuum

Roomba i7+

Roomba i7+ robot vacuum overall

Roomba S9+

Roomba S Robot Vacuum Thumb

The Underside

Under the hood, there are a number of smilarities and difference that you may want to consider.

Among the three models, similarities include:

  • Spinning brush: collects debris along edges or in corners
  • Edge sensors: prevents the vacuum from navigating off of edges or other drop hazards
  • Standard brushroll: standard length, situation between the wheels, centrally located
  • Auto Empty suction port: allows debris to be sucked out of the on-board dust bin and depoisted it the charging station dust bin

Roomba j7

Roomba j7 underside

Roomba i7+

Roomba i7+ robot vacuum design

Roomba S9+

Roomba S9 underside

The Differences

#1. Spinning Brush: There is a difference in the length of the bristles on the 3-arm spinning brush. The j7 and i7 have longer bristles since they need them (with the round body) and the S9+ has shorter bristles since it has a D-shaped body.

#2. Brushroll Length: The brushroll on the S9+ is edge-to-edge and located at the front of the vacuum, while the brushroll on the j7 and i7 is located between the wheels (more of the middle of the vacuum) and is shorter in length.

#3. Navigation Wheel: On the i7 and j7, the navigating wheel is located at the front of the vacuum. But on the S9, it is located at the back. Again, this likely has to do with its ability to turn around and easily change direction.

The Controls

All of these models have a basic control system on the face of the vacuum with additional controls accessible through the smartphone app.

The Roomba j7+ robot vacuum has a single button control with an LED light right around it. Of all three vacuums, these controls feel the most “cutting edge”, so to speak.

Roomba j7+ cleaning with light

Both the Roomba i7+ and S9+ use a three-button system, opposed to the one-button control of the j7+. This makes it look a little less simple, but also makes it easier to access the functions directly from the vacuum and not always need to use the Roomba app on your smartphone.

The 3 buttons for the Roomba i7+ and S9+ offers buttons for the following functions:

  1. Start / Pause a Cleaning
  2. Home / Dock
  3. Spot Cleaning
Roomba S9 button
controls on the Roomba S9+

Since the S9+ is a D-shaped vacuum, the controls are located in the far right corner.

The Brushroll

The brushroll of the Roomba j7+ and i7+ are basically identical. The system uses two rubberized brushrolls that rotate opposite directions of each other to help pull debris into the dust bin.

Two rubber brushrolls are used to agitate dirt and debris off of the floor
Two rubber brushrolls are used to agitate dirt and debris off of the floor

The brushroll on the S9+ is a little different since it is located at the front of the vacuum. This allows the rollers to be longer since the wheels aren’t in the way.

Roomba S9+ brush roll
Roomba S9+ brush roll

And as you’d expect, longer brushrolls mean greater area coverage and shorter run times.

Size & Dimensions

The exact dimensions of these three robot vacuums are pretty comparable:

Roomba j7+

  • 13.34″ diameter
  • 3.3″ tall
  • 7.49 lbs.

Roomba i7+

  • 13.34″ diameter
  • 3.6″ tall
  • 7.44 lbs.

Roomba S9+

  • 12.25″ diameter
  • 3.5″ tall
  • 8.15 lbs.

Of the three, the Roomba S9+ is the smallest (in diameter) compared to the others, but also weighs the most. The Roomba j7+ is the shortest (by about 1/4″) and the Roomba i7+ is the lightest (.05 lbs. lighter than the j7)

Roomba comparison
Roomba comparison

Aside from the size of the robot vacuum itself, you also have to consider the size of the charging station.

All three of these models come with the self-emptying charging station, but not all bases are the same size.

The Roomba S9+ and i7+ use the standard self-emptying base and the Roomba j7+ uses a more compact base.


(i7+ and S9+)

Roomba I Robot Vacuum Product
Capacity: 30 days



Roomba j7+ robot vacuum
Capacity: 60 days

The taller bin can store up to 30 days of debris and the more compact bin can actually store up to 60 days of debris.

Both systems are easy to empty and use disposable debris bags.

Roomba i / s series clean base bag
‘Clean Base’ bag
Roomba i3+ clean base with self empty dust bin
Debris bag fitted into ‘Clean Base’
clean base disposable bags
Bags sold separately

How do the Regular & Plus Model Versions Compare?

Roomba j7 vs j7+

The Roomba j7 and j7+ robots are identical. The only difference is the j7+ model includes a self-empty clean base, while the j7 model does not. Accessories, suction, features, and hardware are 100% identical beyond that.

Roomba S9 vs. S9+

Similarly, the only difference between the S9 and S9+ is the self empty base. The S9+ includes a self-empty base. The S9 does not. The robot itself is exactly the same between the two models

Roomba i7 vs i7+

Just like with iRobot’s other top models, the only difference between the i7 and i7+ is the self empty base. The Roomba i7 does not include a self empty base. The i7+ does include a self empty base. The robot itself is identical between the i7 and i7+.

Top Features

So looks aside, let’s talk about the best features. Are there big differences in what each of these vacuums do? All three have similar cleaning performance, run time, specifications, etc. So what sets each model apart?

Automatic Dust Bin Disposal slot
Automatic dust bin emptying on the Roomba S9+

Here’s a quick list of how they compare.

All three Roombas have:

  • Smart mapping
  • Zoned cleaning
  • App control
  • Scheduled cleanings
  • Voice control (when paired with a smart device)
  • Self-emptying dust bin

Let’s talk about some of the more unique features below:

#1. Self-Emptying Dust Bin

All three of these Roombas offer one of the most attractive features that Roomba has offered to date—a self-emptying dust bin.

Smart charging base included with the Roomba i7+
Smart charging base included with the Roomba i7+

How does it work?

The self-emptying dust bin is designed into the charging base.

When the robot comes back to the dock to charge, a suction system removes the debris from the on-board dust bin and deposits it into a disposable debris bag located in the larger dock.

Roomba S9 Plus dust bag
Debris bag for the Roomba i7+ and S9+ docking station

This debris bag can hold up to 30 loads of debris (on the S9+ or i7+ base) or up to 60 loads of debris (on the j7+).

#2. Smart Control

You can use voice control (when paired with an Amazon Alexa or Google Home device) or smartphone control to communicate with your robot.

How does the app work?

All three of these Roombas also run off of the iRobot smart app. Syncing the vacuum to your smartphone allows for additional features like:

  • Start or pause a cleaning
  • Send robot back to base
  • Track history of cleaned area
  • Track amount of time cleaning
  • Error reports
  • Maintenance
Roomba i3+ Digital Mapping
Roomba Digital Mapping
Roomba i3+ cleaning history
Roomba Cleaning History

Mapping & Navigation

Again, we see more similarities with these three Roombas. They all run on the same mapping and navigation technology with one difference—obstacles avoidance.

The Similarities

All of these Roombas have the following functions when it comes to how they navigate and map a space:

  • On-board camera (maps the ceiling as it cleans)
  • Straighter line navigation
  • Digital mapping (accessible in the app)
  • Imprint Smart Mapping
  • Imprint Link
Under neither the hood on the Roomba S9+
Under the hood of the Roomba S9+ robot vacuum

What is Imprint Mapping?

Imprint mapping allows you to assign room names to spaces, after it has generated an initial base map to go off of.

With room names in place, you can generate Zoned Cleaning cycles and send the Roomba directly to one room in the house for a more targeted cleaning cycle.

iRobot Roomba app smart mapping
iRobot app making a digital map of the Modern Castle home

What is Imprint Link?

Imprint Link technology works with Roomba’s sister line of mopping robots, like the Braava Jet m6. Read our Braava Jet m6 review here.

Braava Jet m6 robot mop

With Imprint Link set up, the Roomba will vacuum the space, return to the dock, and then send a digital signal for the robot mop to start a cycle.

Both of these units communicating with each other prevents the mop from cleaning before the vacuum is done.

The Differences

There are a few differences between the navigation system of these high-end Roombas. Although based on similar technology, the j7+ has a few extra bells and whistles.

#1. Obstacle Avoidance

This vacuum uses the combination of sensors and on-board camera to “see” obstacles and intelligently avoid them entirely. For more sensitive obstacles (ie: pet waste), this technology is priceless.

Roomba j7+ cleaning path - pet waste avoidance

#2. Clean While Away

Another nice feature on the j7+ is the ability for the Roomba to track your location and only clean while you’re away. This prevents the vacuum from being in the way or having the noise of the vacuum disturb you.

The j7+ does this using geofence technology connected to your smartphone. Essentially, when you phone leaves the geofence set around your home it knows it can start cleaning.

Cleaning Performance

Okay, so let’s talk cleaning performance. How good are these Roombas? And do the slight differences in technology drastically change the cleaning performance?

The short answer is no—the j7, i7, and S9 are all excellent cleaners.

The Roomba i7+ comes with enough battery to clean right out of the box

Roomba j7+


Roomba i7+


Roomba S9+


Regardless of what floor type we tested these vacuums on (hardwoods, low pile carpet, or high pile carpet), they did a great job of sucking up all debris.

Roomba S9+ cleaning vs. hardwood floors
Roomba S9+ cleaning hardwood floors

For these tests, we used a variety of debris including cereal, rice, granulated sugar, and kitty litter.

The Winner?

Aside from simply cleaning up the debris, which all three Roombas do exceptionally well, the Roomba j7+ does have a few added features that may enhance performance.

These features include:

  • Obstacle Avoidance
  • Cleaning While Away
  • Larger Debris Capacity (up to 60 days)

Setup & Usability

The setup for these Roombas is easy and quick. For a basic idea of setup, follow the steps listed below:

  1. Unbox the vacuum and remove all packaging.
  2. Charge it up to prepare for a full cleaning. This is an important step to make sure it has enough juice to map your areas properly.
  3. Install the app onto your smartphone.
  4. Follow the in-app prompts to join the app to your vacuum.


Robot maintenance is an important part of any robot vacuum, but it is a bit easier with these higher-end Roombas. Maintenance tasks include the following.

#1. Empty the docking station.

Although all of these Roombas has a self-emptying dust bin system, you’ll still need to empty the debris bag from the ‘Clean Base’ docking station.

As mentioned above, the base of the i7+ or S9+ will hold up to 30 days worth of debris. And the base of the j7+ will hold up to 60 days with of debris.

Roomba i7+ vs. S9+
Roomba i7+ (right) vs. S9+(left)

For less maintenance in this category, go with the Roomba j7+.

#2. Clean the filter.

You will also have to take time to clean the filter regularly. This generally just involves removing the filter, and knocking it on the side of a trash can, or using a brush cleaning tool to clean it. Replace as needed.

Replacing the filter on the Roomba S9
Replacing the filter on the Roomba S9

Although each of these Roombas don’t all use the same filter, the act of maintaining them is still the same, and equally as important regardless of model.

#3. Maintain the underside.

Be sure to check the underside of the vacuum regularly for blockages in the brushrolls, spinning side brushes, or wheels.

All of the Roombas in this comparison have basically the same underside parts so there is not really a difference in the level of maintenance here.

Roomba S9 spinning side brush

Even with proper maintenance, every robot vacuum will still age and eventually, the technology becomes outdated. To avoid your robot going obsolete, you may want to consider the iRobot Select Membership.

iRobot Select Membership

The Roomba Select Membership program started October 5, 2021 and currently is only available with the Roomba j7 or j7+.

iRobot Select Membership
iRobot Select Membership Details

Basically, a Roomba membership allows you to pay $99 (for the j7+) or $0 (for the j7) and then $29 / month to get a new Roomba j7+ / j7.

Along with your new vacuum, you will also get the following benefits:

  • In-app notifications when you need new accessories (bags, brushes, etc.)
  • Accessories aitomatically shipped to you
  • Enhanced protection plan
  • Customer service support team
  • Option to upgrade your robot every 3 years

Which one should you buy?

Ok, so we’re at the end of this comparison—still not sure which model is right for you? Depending on what exactly you’re looking for, you may find that one Roomba to edges out the others.

Roomba j7+ docked at charging station

The Roomba j7+ is the best pick if you’re looking for:

  • Smart Membership: If you don’t want the initial stick shock of purchasing a Roomba outright, the Smart Membership is a great option. Get all the benefits of a robot vacuum, at only $29/mo. as well as the ability to upgrade your robot every 3 years.
  • Less maintenance: The 60-day capacity of the dust bin is double the capacity of the i7 or the S9. This means less time tending to your Roomba.
  • Obstacle avoidance: Obstacle avoidance is another great feature of the j7. Especially if you have pets, this lets the vacuum navigate more intelligently while it’s cleaning.
Roomba i7+ Robot Vacuum

The Roomba i7+ is the best pick if you’re looking for:

  • Lower cost: This model has the lowest price of all three. It does lack some features, like obstacle avoidance (j7 only), wider brushroll (S9 only), as well as a little suction power, but the cleaning performance was still on par with the other models.
Roomba S9+ cleaning hardwoods

The Roomba S9+ is the best pick if you’re looking for:

  • Faster cleaning cycles: Because the S9+ had a wider brushroll, that means it can clean the same amount of square footage in less time. If you want a vacuum that gets the job done faster, the S9+ is a nice choice.
  • Most suction power: If you have carpets and lots of food traffic the extra high suction power may be worth the higher cost.
  • D-shaped body: The S9 also has the D-shaped body style which poses some advantages for cleaning corners and edges.

The Reviews

To read more about each of these three Roombas separately, check out their individual reviews below:

Testing Note – our scores for the j7+ are estimates based on our experience with the Roomba i, s, and e platforms. We have a j7+ in the mail. As soon as it arrives we will test and update this review to confirm our estimations.

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.