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Oral-B iO Series 6 Rechargeable Electric Toothbrush vs Oral-B iO Series 9 Rechargeable Electric Toothbrush

Which one has the downsides you can live with?

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The short answer

Oral-B iO Series 6 Rechargeable Electric Toothbrush ranks higher (#1 vs #2 of 10) and scores better on battery, ease of use. Oral-B iO Series 9 Rechargeable Electric Toothbrush wins on durability.

The biggest complaint about the Oral-B iO Series 6 Rechargeable Electric Toothbrush is costs much more, with io-only heads; for the Oral-B iO Series 9 Rechargeable Electric Toothbrush it's very expensive. Pick the one whose catch bothers you less.

#1 of 10 · $$Oral-B iO Series 6 Rechargeable Electric Toothbrush

Good for: A visible pressure light that also flags too little pressure

Its catch: costs much more, with iO-only heads

Check price on Amazon
#2 of 10 · $$$Oral-B iO Series 9 Rechargeable Electric Toothbrush

Good for: People who want app coaching and data

Its catch: very expensive

Check price on Amazon

Paid links. We don't list prices — they change daily. Neither one feels right?

Side by side

Oral-B iO Series 6 Rechargeable Electric ToothbrushOral-B iO Series 9 Rechargeable Electric Toothbrush
Rank in electric toothbrushes#1#2
Price tier$$$$$
TypeOscillatingOscillating
Amazon 1–2★ share8%6%
Overall score3.93.8
Cleaning feel4.54.5
Gentleness4.54.5
Battery4.03.0
Replacement head cost2.52.5
Ease of use4.54.0
Durability3.54.0

Price tiers: $ under $50 · $$ $50–120 · $$$ over $120. Highlighted = clearly better (a score gap of 0.3 or more, or a 1–2★ share at least 3 points lower). Scores are explained, with sources, on each product's page.

Top complaints

Oral-B iO Series 6 Rechargeable Electric Toothbrush

  • Costs much more, with iO-only heads

    Wirecutter says it regularly costs three times as much as the Pro 1000 and its heads cost more than double; standard Oral-B heads don't fit iO models. Electric Teeth lists the iO-specific heads and the non-essential Bluetooth as its cons.

    Source: Wirecutter, Electric Teeth (Oral-B iO6 review)
  • Gunk builds up at the head mount

    Wirecutter notes some customer reviewers clean the junction between head and handle daily, and Electric Teeth says the attachment point can collect mold if not cleaned regularly.

    Source: Wirecutter, Electric Teeth (Oral-B iO6 review)
  • Drooly brushing for some, slow charging

    The size and shape of iO heads gave some Wirecutter testers a more drooly experience than the Pro 1000. Electric Teeth says a full charge takes up to about 12 hours.

    Source: Wirecutter, Electric Teeth (Oral-B iO6 review)

Oral-B iO Series 9 Rechargeable Electric Toothbrush

  • Very expensive

    CNN Underscored calls the roughly $330 list price a tough sell even on discount. Electric Teeth puts the US suggested price at $299.99. Amazon's summary says value for money is mixed, with some owners finding it overpriced.

    Source: CNN Underscored, Electric Teeth, Amazon.com product page (Customers say)
  • iO-only heads and a mold-prone gap

    Electric Teeth puts iO heads at about $8, roughly twice the price of standard Oral-B heads, and says mold can build up in the gap around the magnetic head mount. Wirecutter notes some customer reviewers clean that junction daily.

    Source: Electric Teeth, Wirecutter
  • Tracking accuracy disputed

    Electric Teeth found position tracking inconsistent, sometimes logging the wrong zone, and worse for left-handed users. CNN Underscored, by contrast, found the app accurate every time it tested it. Amazon's summary calls tracking mixed.

    Source: Electric Teeth, CNN Underscored, Amazon.com product page (Customers say)
  • About 12 days per charge

    Electric Teeth usually got about 12 days against a 14-day claim, though the charger refills it in about 3 hours. Amazon's summary says some owners report it doesn't hold a charge.

    Source: Electric Teeth, Amazon.com product page (Customers say)

Who should pick which

Pick the Oral-B iO Series 6 Rechargeable Electric Toothbrush if

  • A visible pressure light that also flags too little pressure

  • A quieter Oral-B

  • Timer and battery display without needing the app

Skip it if: You want the cheapest heads; You don't want to clean the head mount often; You only need the basics (the Pro 1000 covers them)

Check price on AmazonAll complaints →

Pick the Oral-B iO Series 9 Rechargeable Electric Toothbrush if

  • People who want app coaching and data

  • Building better brushing habits

  • Oral-B users who want the quieter iO motor

Skip it if: You won't use the app; You're on a budget; You're left-handed and want reliable position tracking

Check price on AmazonAll complaints →

We don't list prices — they change daily. Paid links.

Neither one feels right?

If both catches are deal-breakers, start here.

Best value · #4 in electric toothbrushesAquaSonic Black Series Ultra Whitening Toothbrush

Amazon's most-rated electric toothbrush comes with 8 heads, a travel case and a month-plus battery. Testers found it feels cheaper and less gentle than Sonicare or Oral-B, and it has no pressure sensor.

Its catch: intense vibration, not very gentleA third option · #3Oral-B Pro 1000 Rechargeable Electric Toothbrush

Wirecutter's long-running top pick, with cheap, widely available heads. It is louder than sonic brushes, and its pressure alert is easy to miss. Owners also report units that stop holding a charge.

Its catch: stops holding a charge or dies earlyAll 10 comparedSee every electric toothbrush, ranked

Each one's biggest complaint at a glance, with the full ranking.

Browse electric toothbrushes →

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