Oral-B iO Series 3 vs Philips Sonicare 3100
Over three years, with heads at each maker's own pack price, the Philips Sonicare 3100 costs about $113 to the Oral-B iO Series 3's $139. Both have pressure sensors, signalled differently: multi-signal pressure sensor on the Oral-B iO Series 3, pressure sensor (vibration or sound) on the Philips Sonicare 3100. The Oral-B iO Series 3 has an ADA Seal listing; none was found for the Philips Sonicare 3100. They also move differently: see the oscillating-versus-sonic explainer for what the evidence does and doesn't say about that. Every other published figure for both is in the table, with the rows where they differ tinted.

Oral-B
Oral-B iO Series 3
~$60
At the snapshot price this was the cheapest iO handle on oralb.com, a few dollars under the iO2.
Best for: The cheapest way into the iO head and pressure light

Philips Sonicare
Philips Sonicare 3100
~$40
What the 3100 adds over the 1100 is a pressure sensor: the handle vibrates when you press too hard.
Best for: A Sonicare pressure sensor at the lowest price
| Specification | Oral-B iO Series 3 | Philips Sonicare 3100 |
|---|---|---|
| Approx. price | ~$60 | ~$40 |
| 3-year cost | ~$139 ($60 handle + 11 heads at $7.22) | ~$113 ($40 handle + 11 heads at $6.66) |
| Type | Oscillating-rotating | Sonic |
| Motion | Oscillating-rotating (round head) | Sonic (vibrating head) |
| Motor | iO magnetic drive | not published |
| Pressure sensor | Multi-signal pressure sensor: Visible iO pressure sensor signals too little, the right amount of, or too much pressure | Pressure sensor (vibration or sound): Vibrates the handle to alert you when brushing too hard |
| ADA Seal | Listed: Oral-B iO Series | No listing found |
| Timer | 2-minute timer | 2-minute timer |
| Quadrant pacer | not published | Yes, every 30 seconds |
| Modes | 3: Daily Clean, Sensitive, Whitening | 1: Clean |
| Screen | None | None |
| App | not published | No |
| Battery | not published | 14-day battery (Philips spec: operating time up to 14 days) |
| Charging | charging stand | not published |
| Travel case | No | No |
| Heads in the box | 1 | 1 |
| Head family | Oral-B iO | Sonicare click-on |
| Head compatibility | Takes Oral-B iO heads only; non-iO Oral-B heads do not fit | Any Philips Sonicare click-on head (C1 SimplyClean, C2, C3, G3, A3, W); not Philips One heads |
| Price per head | $7.22 (Oral-B iO Ultimate Clean 9-count, $64.99 on oralb.com) | $6.66 (Sonicare SimplyClean 6-pack (HX6016/77), $39.96 on usa.philips.com) |
| Replace heads every | 3 months (maker) | 3 months (maker) |
| Warranty | 2 years | 2 years |
| First listed | not published | 2021 |
Oral-B iO Series 3: what it gives up
- No travel case and no app described; the iO4 adds both for $40 more
- No battery figure, where the iO2 next to it gets four weeks
- The price is a sale figure and may climb back above the iO2's
Philips Sonicare 3100: what it gives up
- One mode; a Gum Health setting starts with the $60 Sonicare 5000
- Philips lists it as support status, so stock may not last
- No brush-movement figure published
- Sonicare saves the travel case and app for adult handles from the $130 Series 6500
Full pages: Oral-B iO Series 3 · Philips Sonicare 3100