Feno is on a mission to transform oral health and unlock its potential to revolutionize overall systemic health. By harnessing cutting-edge technologies and proprietary formulations, Feno has developed an innovative connected smart toothbrush that provides a comprehensive and efficient oral care solution, delivering a thorough cleaning in just 20 seconds.
Feno (feno.co) has 93 customer reviews on Five Star Index, with an average rating of 4.6 out of 5.
Also known as
feno.co
Website
feno.co
Category
Dental Services
Location
Culver City, California
Listed on Five Star Index
2026
About these reviews
Replies
The company replied to 15% of reviews.
Latest
Most recent review: October 2026.
Edits
Reviews are shown as their authors wrote them. The company can reply, but cannot edit them.
Score
This company cannot pay to remove reviews or change its score.
Too hard to use. I just threw it in the trash. They want you to spend $8 to get some daily evaluation. I just want to brush my teeth.
Response from FenoSep 10, 2026
We are sorry to hear the experience felt frustrating and more complicated than it should have. You should be able to simply use your Feno Smartbrush for brushing without needing the additional subscription features.
We’d really appreciate the opportunity to help you get set up and make the experience easier. Please reach out to our support team, and we’ll be happy to walk you through it personally.
DE
Declan
Feno… WE KNOW
Ordered over a month ago and have yet to receive any information on my package. Also the tracking link on my package just stopped working and when I try to track it via the feno website, it’s says order not found. I am baffled by the lack of honesty and communication.
Response from FenoJul 20, 2026
Hi Declan,
We're sorry for the trouble here. After looking into this, we weren't able to find any order matching your details in our system — and it appears the site you ordered from isn't us. Unfortunately there are counterfeit websites impersonating Feno that aren't connected to our company, which would explain the missing order and the broken tracking.
Our only official store is feno.co. To help recover your payment, we'd recommend disputing the charge with your bank or card provider (or through PayPal, if that's how you paid). We're also actively working to get these fake sites shut down.
If there's anything we can do, reach us at [email protected] and we'll help however we can.
— The Feno Team
JA
Jake
Zero
Zero stars if I could. I ordered from Feno over two months ago. After waiting with no updates, I was finally told by their customer experience team that they were dealing with a "temporary stock issue". They tried to smooth it over by offering extra Feno Foam, but it's been over two months now and the item still hasn't even shipped, with no communication in between. It is completely unacceptable to take customers' money for items you don't actually have in stock to fulfill. I have officially requested a cancellation and a full refund. Avoid this company unless you want your money tied up for months.
Response from FenoJun 2, 2026
Hi Jake,
First off, we're sorry. This is not the experience we want for anyone, and we completely understand your decision to cancel — your full refund is on its way.
Feedback like yours is exactly what helps us get better, and we've taken it to heart. We're tightening up our order tracking and customer updates for international orders as a result.
Thank you for the honest feedback, Jake. It matters to us.
— The Feno Team
DM
David M.
Complete Disaster
This is my second review. The first one explained how feno's blinkered focus sells to everyone as if we are all in the US, but anyone buying outside the US will not get the same treatment.
Everything they post takes months to arrive. The most recent shipment still hasn't arrived 2 months after it was sent. This is no longer a problem as I am no longer using the device, but it's a good indication of the inefficient service they offer.
So why a second review?
When you buy a feno they give you this whole story about an AI scanning process that can accurately measure which mouthpiece personally fits you. This turns out to be a process where they take a photo and then manually guess. I got sent 2 mouthpieces with the original purchase, neither fit correctly. I asked for sizes but they refused and then sent another mouthpiece that also didn't fit. They then sent the actual measurements by which I could see why none of them fit, and the last choice of mouthpiece size was posted (the item that has never arrived) So during this multi-month-long waiting process, I was using the best fitting mouthpiece that wasn't quite the right size, did not account for overbite misalignment between upper and lower teethlines and it damaged an implant that will now cost me about £4000 to fix. My implant was not lose beforehand, but it is now, caused by the shaking motion. There's nothing worse than spending so much time, effort and money to improve things, and the knowing that your own decisions have made it worse.
So you should be very careful when considering whether to use this toothbrush. It's basically a mouthpiece that's being shaken from side to side, there is no 'intelligence' to it, especially when it comes to mouthpieces. Their claims of matching shapes and sizes to a large dataset appears to be complete sales talk, because none of the mouthpieces I was sent even reach the last molars, all of them might be suitable for 28 teeth (perhaps thats a norm in the US) but they do not clean all 32 and they basically have 5 fixed size options. All mouthpieces I was sent assume a perfectly aligned bite, and if you have an overbite the pressure is not as intended.
I didn't write this review straight away because I was so angry. If I lived in the US I have no doubt I would be suing them for damages, and I consider they got off lightly by just giving me a full refund, but that does not come close to the dentist bill I now face to repair the damage.
In summary, for me a complete financial and dental disaster.
If you already have strong health teeth and a perfect bite, this idea might work for you. If you have overbite, implants, other structural dental work or anything lose in your mouth I would recommend you stay away.
Response from FenoJun 2, 2026
Hi Dave, thank you for the detailed feedback, and I'm sorry for the experience overall. On shipping, you're right — the international delays you describe, including the shipment that hasn't arrived, are not the standard we hold ourselves to, and we're working to improve fulfillment outside the US.
I'm sorry to hear about your implant. We take any concern like this seriously and want to understand it fully. Established clinical guidance indicates that a fully integrated implant isn't loosened by toothbrush vibration, but every situation is different and I don't want to dismiss yours — if you're willing, please share your dentist's assessment with us directly at [email protected] so we can review it properly.
On sizing, the fit clearly didn't work for you, and that feedback genuinely helps us improve our mouthpiece range. We've issued your full refund, and I'd welcome the chance to follow up with you privately. — Kenny, Feno
BC
BC
Never delivered - scam
I ordered over a month ago with a promise of delivery within 3-7 days. Now they still have not shipped my order. Their support is useless. I have asked for a refund twice now and they have not responded. On top of this, you have to pay a subscription (which I also had to pay before them shipping). Overall awful experience.
Response from FenoApr 30, 2026
Hi BC,
Thank you for taking the time to share your feedback, and we're truly sorry for the frustration here. Based on the details, it looks like you may be writing from Switzerland — international orders do take longer to arrive than US orders, as outlined in our international shipping policy.
That said, we'd love the chance to make this right. If you could identify yourself by emailing our support team with your order details, we'll look into your shipment, expedite where possible, and follow up on your refund request right away.
Looking forward to hearing from you.
BA
Bailey
Falls way short, app is garbage
Great product in theory, but falls short. Mouthpiece is very large and uncomfortable, and actually made canker sores in the back of my mouth from the friction of the mouthpiece the very first week.
Even turning the vibration setting to low for 20 seconds still create the same friction areas.
8/10 Cleaning. Often times will miss spots I can still feel plaque on. Sometimes need to brush twice in a row in order to get that clean mouth feeling and all of the plaque off.
The app 0/10. This is where the product falls short the most. Scans are simply photos of your mouth you take yourself. Wildly inaccurate! Used my product and it said I had multiple cavities, plaque, and tooth fractures on the first scan and more issues would pop up with each consecutive scan, giving me a lower dental score each time. And it doesn’t tell you specifically where these “lesions “are, only the side of the mouth they are located on. I immediately made a dental appointment and had none of those issues at all! The dentist actually saying that I had “superior dental .” The app created so much stress and made me super insecure about Poor dental health and negatively impacted my self-esteem for an entire three weeks.
Additionally, the fresh breath score is totally off despite using it for three weeks consistently 2 to 4 times per day I’ve never gotten over a 50/100.
Product OK at best, app is total garbage and if anything negatively impacts your overall well-being creating a false sense of insecurity.
Response from FenoMar 3, 2026
We’re really sorry to hear about your experience. That’s not the kind of impact we ever want Feno to have — especially when it comes to your comfort and peace of mind.
If the Mouthpiece felt too large or caused friction, that’s often a sizing issue. Fit is critical for both comfort and effectiveness, and we’d genuinely like to help you explore a different size to see if that improves your experience.
Regarding the scan results, Feno is designed to flag potential areas to monitor — not to provide a diagnosis. We understand how concerning unexpected results can feel. If the scans seemed inaccurate or unclear, our support team can help guide you through best practices to improve scan accuracy and ensure the app is functioning as intended.
Please reach out to us directly at [email protected] so we can personally assist you with mouthpiece fit, cleaning optimization, and a deeper review of your app experience.
We appreciate you sharing your feedback — and we’d welcome the opportunity to support you properly.
HM
Harper M. C.
I had a very disappointing experience…
I had a very disappointing experience with this company.
I requested to cancel my order before it was fulfilled and clearly explained the reason when asked. After that, communication stopped. Emails were not answered, and when I tried calling, no one picked up. Instead, I received an automated message saying phone support is unavailable and to contact them via text or email — which I had already done, multiple times.
Despite following their instructions and providing everything they asked for, I received no confirmation of cancellation or refund. I was forced to open a PayPal Credit dispute just to protect myself.
This experience caused unnecessary stress and wasted time. A legitimate company should not ignore customers once payment is made, nor make support inaccessible. I would strongly caution others before ordering.
Tugba ugurlu
Response from FenoJan 20, 2026
Hi Harper — we’re truly sorry for the frustration you experienced. That’s not the experience we want for anyone.
We’ve reviewed our records but can’t locate an order under this name. Please note there are unaffiliated third-party sites selling products claiming to be Feno, which we are not connected to. That said, we genuinely want to help.
Our phone support is limited, which is why calls may route to email/text, and we understand how frustrating that can be. If you purchased directly from Feno, we’d like to investigate and resolve this properly.
Please contact us at [email protected] with any order details or receipt so we can assist.
TS
Tom S.
CON EMAIL BOUNCES INSTA NOT LINKED
CON EMAIL BOUNCES INSTA NOT LINKED. Took my money and no product, trying to get my money back from American Express!
Response from FenoMay 7, 2025
Hi Tom, we're truly sorry to hear about your experience. This definitely doesn’t reflect the standard we strive for at Feno. It looks like our team connected with you about a month ago and resolved the initial issue—but if you're still facing problems, we want to make it right. Please reach out to us directly at [email protected] so we can assist you right away. We're here to help.