UPDATE: Oct. 8, 2024, 10:00 a.m. EDT iRobot announced a new robot vacuum, the Roomba Combo 10 Max Robot + AutoWash Dock, over the summer. We are in the process of testing it hands-on and will update this guide accordingly.
It would come as a surprise to more people than you think that "roomba" isn't the universal term for a robot vacuum. It is, in fact, a capital "R" that denotes Roomba as a proper noun rather than a generic trademark, though the Band-Aid level interchangeability really does exemplify just how iconic iRobot has become in the world of automated floor cleaners.
That can be attributed to the fact that iRobot has consistently delivered some of the most reliable robot vacuum models for two decades. More than 20 Roombas have come out since the first one hit homes in 2002, but tracking the best Roombas isn't so chaotic when you consider that only a handful of those models are actually relevant at the time of your shopping.
How to tell the difference between the Roomba models
The arbitrary numbers and letters of the Roomba family tree are confusing at face value, but nothing that can't be told apart after learning a few super general classification themes.
When shopping for a Roomba, you'll really only be choosing from what I call iRobot's core lineup: the group of three to five Roomba series that are actively sold on iRobot's website. Any Roomba whose title includes a letter and a number (like j9+ or i5) or the word Max is more advanced than a Roomba with just numbers in the title (like 692) or just a plain name (like Roomba Vac).
The j Series is iRobot's most advanced right now, followed by the s Series, i Series, and then the 600 Series. A plus sign (like j9+) denotes that the model comes with a self-emptying dock. Roombas that mop will have "Combo" in the title, and there are several Roombas that can be purchased with or without mopping abilities. "Max" is a new layer of Roomba typology that was introduced with the drop of the Roomba Combo 10 Max — it refers to the ability for a mopping Roomba to wash and dry its own mopping pads within the self-empty dock.
Do Roombas go on sale for Prime Day?
Yep, many of the main Roombas in this guide will be on sale for Prime Big Deal Days on Oct. 8 and 9. (Prime events are huge for Roombas despite the fact that Amazon and iRobot ditched their acquisition plan.) Speaking of that new Roomba Combo 10 Max that just came out a few weeks after Prime Day in July, it's seeing a big Prime Day discount. I didn't expect it to go on sale for October Prime Day at all, let alone drop under $1,000. Mashable will be tracking deals on Roombas daily throughout the week of Prime Big Deal Days, plus deals on any other big robot vacuum deals from Roborock, Shark, eufy, and more.
Not sure which Roomba to scope out on Prime Day? We've laid out an exhaustive guide of all of the Roomba models below, where we cover the fine print, like which Roombas have smart mapping or small obstacle detection, in our deep dive into the Roomba lineup below, noting the most important differences between each current Roomba.