Roborock S8 Pro Ultra vs iRobot Roomba j9+: Which Robot Vacuum Wins?

These are the two robot vacuums people cross-shop at the premium end, but they aim at different buyers. The Roborock S8 Pro Ultra is a do-everything machine with real mopping and a dock that maintains itself; the Roomba j9+ is a focused, dependable vacuum with iRobot’s long track record. We ran both daily for two months, and the choice is mostly about how much you value mopping — and how much you want to spend.

What each robot is really for

The Roborock is a vacuum-and-mop hybrid with a dock that refills and cleans the mop itself, aimed at people who want one machine to handle hard floors completely. The Roomba j9+ is a vacuum first and only — no mopping — backed by iRobot’s mature navigation and a base that empties itself for weeks. Deciding whether you want serious mopping settles most of this comparison before you look at any other spec.

Vacuuming performance

Both clean floors well, but the Roborock’s higher suction gives it an edge on carpet and in corners, and it pulls embedded pet hair a little better in testing. The Roomba is no slouch — its pickup is strong and consistent — but if raw suction is your priority, the S8 Pro Ultra is the more powerful vacuum. On bare floors the gap narrows and both do a fine job.

Mopping: the Roborock’s decisive advantage

This is where the two part ways. The Roborock actually mops, with a vibrating pad and, crucially, a mop-lift that raises it over carpet so you can vacuum and mop in one pass. The Roomba j9+ does not mop at all. If you have tile, wood or laminate and want a robot that leaves floors genuinely clean rather than just dust-free, the Roborock is in a different category.

Navigation and obstacle avoidance

Both navigate intelligently and map multiple rooms well. The Roomba’s PrecisionVision is excellent at dodging shoes, cords and, notably, pet waste — iRobot backs it with a specific pet-mess guarantee. The Roborock uses lidar plus 3D obstacle sensing and is similarly good at avoiding clutter. This one is close to a tie; both will navigate a real, messy home without constant rescuing.

The dock: self-emptying vs self-maintaining

Both docks reduce chores, but the Roborock’s does more. It empties the bin, then washes and dries the mop so you are barely involved for weeks. The Roomba’s Clean Base empties debris into a bag that lasts around 60 days — excellent, but vacuum-only because there is no mop to maintain. More automation is one reason the Roborock costs what it does.

Price and value

The Roomba j9+ costs roughly half as much, and if you only need reliable vacuuming with a self-emptying base, it is the better value — you are not paying for mopping hardware you will never use. The Roborock justifies its higher price only if you genuinely want the mopping and the self-cleaning dock. Match the spend to the features you will actually use.