Oral-B iO7 vs Oral-B iO9: Which smart electric toothbrush is best? (2025)

Oral-B’s iO7 and iO9 were some of the first brushes to launch in the iO series, and addressed one of the biggest complaints that people have with electric toothbrushes – that they can be too harsh on teeth and gums. It did this with the introduction of micro vibrations, a technology which also made the brushes much quieter, too.

Like the rest of the iO series, from the iO2, the newest, cheapest (and best, according to our tech critic Steve Hogarty), to the top-of-the-range iO10 – they come with “AI brushing recognition technology”. In other words, there’s an accompanying app that tracks how you brush each zone of your mouth.

Inside the handle of the iO toothbrushes there is both a gyro sensor and accelerometer, and a portion of Oral-B’s development period was spent collecting data on people’s brushing habits so that the algorithm could accurately read where the brush was in the mouth of the user and interpret it to show how effective their brushing had been.

The iO9 can even track 16 “sub-zones”, meaning it’ll know if you’re getting to each surface of every tooth. This may seem like an over-complication, but neglecting the harder-to-reach surfaces of the mouth, like the underside of the molars, is one of dentists’ biggest gripes.

There’s a difference in price between the iO7 and the iO9, but what exactly sets these two brushes apart? And is it really worth paying extra for what the iO9 has to offer? I used both of these brushes to find out, assessing them on their brushing modes, customisation, the limitations of the AI and charging speeds. Here’s how I got on.

How I tested

I used both Oral-B brushes and assessed them carefully on the criteria below.

• User experience: While using both of the brushes, I assessed how easy they were to brush with, noting any design features that improved the user experience. I downloaded the corresponding app and used it as you will be using it at home, assessing how well the features worked in practice, and how nice it was to use, noting any lag or other issues.
• Cleaning power: I made a note of how my mouth felt after brushing with the two brushes.
• Modes: I used and compared the cleaning modes available when using each brush, and thought about how useful and necessary they were. I also thought about what the everyday user would get out of using each brush and whether it was worth it for the price.
• Battery life: I charged the battery up to full and noted how practical this was, noting whether there was a compatible charging case then timed how long it lasted before needing to be recharged. I also noted whether it came with a charging case.

Why you can trust IndyBest reviews

Jon Axworthy has been reviewing products for nearly 30 years, so he knows how to cut through the noise and get to the interesting bits, from what a product is like to use to whether it is genuinely worth its price tag. Jon has incorporated these brushes into his everyday routine and used them as you will be at home, meaning they have gone through thorough, real-world testing. If you’re unsure on the iO7 or iO9, Jon has also shared his verdict on other models from leading brands, including Phillips, Ordo and Oral-B.