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Our picks at a glance
- 1Best OverallWaterpik Aquarius Countertop Water Flosser4.6158,630 ratingsSee it on Amazon
- 2Best CordlessCOSLUS C20 Water Dental Flosser4.454,817 ratingsSee it on Amazon
- 3Best for TravelWaterpik Cordless Pearl Portable Water Flosser4.320,230 ratingsSee it on Amazon
These three cover both countertop and cordless designs. The Waterpik Aquarius is a countertop unit with 10 pressure settings and 7 tips, the COSLUS C20 is a cordless flosser with a 300 ml tank, and the Waterpik Cordless Pearl is a cordless model its listing calls extra quiet. Each is rated 4.3 or higher across more than 20,000 ratings on Amazon.
How we picked
We searched Amazon for water flossers, set aside sponsored results, string flossers and toothbrush-and-flosser combos, and kept listings rated 4.3 or higher across at least 200 ratings. Then we saved each finalist's title, bullets, specification fields, seller and return terms.
Pair one with a brush from the best electric toothbrushes, or see how two popular brushes compare in Oral-B vs Sonicare.
Waterpik Aquarius Countertop Water Flosser
The most rated of the three by a wide margin, at more than 158,000 ratings. Waterpik lists 10 pressure settings, a massage mode, a timer that pauses at 30 seconds and 1 minute, a 22 oz removable reservoir it says gives 90+ seconds of use, 7 tips and 360-degree tip rotation. It plugs into the wall (the listing says 120VAC/60Hz, for use in North America only) and carries a 3-year limited warranty. Waterpik says it was the first water flosser brand to earn the American Dental Association Seal of Acceptance.
What the listing says
- 10 pressure settings plus a massage mode
- 22 oz reservoir; 90+ seconds per fill (per Waterpik)
- 7 tips; 360-degree tip rotation
- Plug-in, for use in North America only
- 3-year limited warranty (per Waterpik)
Shipped and sold by Amazon.com, with free 30-day returns, per the listing.
COSLUS C20 Water Dental Flosser
A cordless flosser with what COSLUS lists as a 300 ml tank. It has three modes, five interchangeable tips, an IPX7 rating that COSLUS says makes it safe to use in the shower, and USB charging, with no wall adapter included. COSLUS says a 3-hour charge gives 30 days of use. The battery is described two ways: the bullets say rechargeable, while a specification field says 1 AA battery. The title calls it ADA Accepted.
What the listing says
- 300 ml tank (per COSLUS)
- 3 modes; 5 tips
- IPX7; shower use per COSLUS
- USB charging; adapter not included
- Title: ADA Accepted
Sold by Awn Tss and shipped by Amazon, with free 30-day returns, per the listing.
Waterpik Cordless Pearl Portable Water Flosser
Waterpik's description calls the Cordless Pearl extra quiet and perfect for smaller bathrooms or travel. It has 4 tips, 2 pressure settings, a 7 oz removable reservoir that Waterpik says gives up to 45 seconds of flossing, USB charging with no wall adapter included, and a 2-year limited warranty. Unlike the COSLUS, its listing says it is not for use in the shower. The battery type disagrees within the listing: NiMH in a bullet, lithium metal in a specification field. Its 4.3 rating sits exactly at our floor.
What the listing says
- 4 tips; 2 pressure settings
- 7 oz reservoir; up to 45 seconds (per Waterpik)
- USB charging; adapter not included
- Not for use in the shower
- 2-year limited warranty (per Waterpik)
Shipped and sold by Amazon.com, with free 30-day returns, per the listing.
Side by side
| Flosser | Type | Reservoir (as listed) | Pressure settings | Seller | Rating |
|---|---|---|---|---|---|
| Waterpik Aquarius Countertop Water Flosser | Countertop, plug-in | 22 oz | 10 | Amazon.com | 4.6158,630 ratings |
| COSLUS C20 Water Dental Flosser | Cordless | 300 ml | Not stated; 3 modes | Awn Tss | 4.454,817 ratings |
| Waterpik Cordless Pearl Portable Water Flosser | Cordless | 7 oz | 2 | Amazon.com | 4.320,230 ratings |
What to look for
Countertop or cordless
The Aquarius plugs in and holds the most water. Both cordless listings describe USB charging, though the COSLUS specification field lists 1 AA battery.
Reservoir
Waterpik says the Aquarius gives 90+ seconds per fill and the Cordless Pearl up to 45 seconds. COSLUS gives its tank size, 300 ml, but no time.
Shower use
COSLUS lists IPX7 and says the C20 is safe to use in the shower. Waterpik says the Cordless Pearl is not for use in the shower.
First use
Waterpik and COSLUS both say to start on the lowest or softest setting and work up.
The bottom line
Frequently asked questions
Countertop or cordless water flosser?
A countertop model like the Aquarius plugs in and holds a bigger reservoir; Waterpik says it gives 90+ seconds per fill. Cordless models like the COSLUS C20 and the Cordless Pearl are described as rechargeable in their bullets (the COSLUS specification field says 1 AA battery) and are easier to travel with.
Can I use a water flosser in the shower?
It depends on the model. COSLUS says the C20 is IPX7 and safe for shower use. Waterpik's Cordless Pearl listing says it is not for use in the shower.
Do the cordless ones come with a wall charger?
No. Both listings say they charge from a USB cable and that the wall adapter is not included.
Can a water flosser replace string floss?
Waterpik's Cordless Pearl listing says its water flossers are clinically proven up to 2X as effective as string floss for removing bacterial plaque. Your dentist can tell you what suits you.
Why are the ratings different from what I see on Amazon?
Ratings change over time. The figures here are what each listing showed on the date at the top of this page.
Ratings and listing details were checked on Amazon on the date shown at the top of this page. We have not used these; everything above is from their Amazon listings.
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