Oral-B iO Series 9 vs Oral-B iO Series 6: choose the right toothbrush for you

Oral-B iO Series 9 and Oral-B iO Series 6 electric toothbrushes
(Image credit: Future)

The Oral-B iO Series are some of the best electric toothbrushes you can buy, with models available for every budget, but some of them can be difficult to differentiate between. The Oral-B iO Series 9 (also known as the iO9) is currently our top-rated toothbrush, but it looks almost identical to the Oral-B iO Series 6 (also called the iO6), so you might be wondering if there's really much of a difference between the two.

The simple answer is yes, if you're a frequent traveller. The main difference between the two is that the iO Series 9 comes with a charging case that will keep it powered up when you're away from home, while the iO Series 9 comes with a simple carry case that'll protect your brush from dust and knocks, but that's it.

There's also a significant difference in price. Both brushes are available much more cheaply now than they were at launch, but the iO Series 9 is still around twice the price of the iO Series 6 in most territories. If you're sticking to a modest budget, then you'd be better sticking with the iO Series 6, or waiting for a sales event like Black Friday or Amazon Prime Day, when electric toothbrushes tend to be steeply discounted.

For a full roundup of all the key similarities and differences, read on. If you're ready to make your choice, we've found the best prices for both toothbrushes right here.

Price and availability

  • Oral-B iO Series 6 is much cheaper
  • Both brushes cheaper now than at launch
  • Often discounted in sale events

The Oral-B iO Series 9 was released in 2020, and was originally priced at $300 / £500 / AU$400. The Oral-B iO Series 6 was launched 2021 for $149.99 / £300 / AU$400.

The iO Series 9 was one of the most expensive electric toothbrushes around when it first launched, but like all brushes, it was soon available much more cheaply at third-party retailers like Amazon. At the time of writing, it's on sale for $250 / £218 / AU$425.

The iO Series 6 has also had a big price cut since launch, and at the time of writing you can grab it for $120 / £110 / AU$225. Both brushes often get even bigger discounts during annual sales events like Black Friday and Amazon Prime Day as well, so if you can wait, you may be able to snag an even better deal then.

Both brushes use the same heads, which cost around $35 / £30 / AU$35 for a set of two, but can sometimes be found more cheaply on Amazon.


  • Brush itself is the same
  • Oral-B iO Series 9 has a charging case
  • Different style charging bases

When it comes to design, these two brushes are nearly identical. Both have sleek, well-balanced handles that take the same type of Oral-B iO head, and feature bright color displays that make it easy to switch between brushing modes.

The big difference is the cases. The iO Series 6 has a simple, lightweight case that serves as a way to keep your brush and two heads safe from dirt and damage. The iO Series 9 has a much more sophisticated case that can keep your brush powered up away from home, and has a USB cable stashed in the base that makes it easy to charge (though there's only room inside for the brush handle and one head).

Oral-B iO Series 9 electric toothbrush in charging case

The Oral-B iO Series 9 has a case that keeps the brush powered up when you're unable to use its charging base (Image credit: Future)

The two brushes also have different chargers. The iO Series 6 has a typical induction charger with a large prong that fits into a recess in the bottom of the brush handle. The iO Series 9, on the other hand, has a charger that resembles an ice hockey puck, and holds the brush handle in place magnetically. This has the advantage of being easier to clean, and there's no hole in the brush handle to gather toothpaste and water residue, though you're also more likely to accidentally knock the brush off.

Oral-B iO Series 6 electric toothbrush in case

The Oral-B iO Series 6 has a very simple plastic case that holds the handle and two heads (Image credit: Future)


  • Both have quiet brushless motor
  • Bluetooth for use with mobile app
  • Pressure sensor

Like all Oral-B iO toothbrushes, the Series 6 and Series 9 both use brushless motors that make them much quieter than the company's earlier models, and allow them to glide smoothly over your teeth. They're not silent, but you should be able to brush your teeth in the morning without waking your partner in the next room.

Like all premium electric toothbrushes, both the iO Series 6 and Series 9 have a pressure sensor in the handle, with a colored LED that alerts you if you're pressing too hard. What's unusual here is that they can also detect if you're not pressing hard enough. When the LED turns green, you've got it just right.

Screengrabs from Oral-B mobile app

The Oral-B mobile app helps ensure you don't miss a spot (Image credit: Future)

Both brushes contain position sensors that can detect which part of your mouth you're currently brushing, and a Bluetooth transmitter that can send this data to the Oral-B app on your smartphone. It might sound like overkill, but once you've tried it, we think you'll be impressed. The app shows your progress on-screen as you brush, helping you thoroughly clean each portion of your mouth and guiding you to improve your brushing technique. It's a genuinely useful feature, and developing better technique will stand you in good stead in the future.

The app also gives you tips to improve your oral health, and kids will appreciate the ability to earn virtual badges for consistently good brushing.

You don't need to use the app every time you brush, though; after each session, the app will give you feedback in the form of an emoji on the screen. A smiley face with stars for eyes indicates a particularly good job,

Cat Ellis

Cat is the editor of TechRadar's sister site Advnture. She’s a UK Athletics qualified run leader, and in her spare time enjoys nothing more than lacing up her shoes and hitting the roads and trails (the muddier, the better)