Circular Ring Review: Is It Worth It?

Circular Ring Slim - Circular Ring Review


The Circular Ring is one of the most well-designed smart rings you can get now. But how does it stack up? In this Circular Ring Review, we dive deeper into the features and functionalities of the smart ring to find out if it’s a good investment.

The Circular Ring is designed to have a thin profile on your finger while still being able to do what a smart ring should—monitor health metrics, wake you up at your preferred time, and so on. It’s the latest smart ring from French company Circular, which released two variants—Circular Slim and Circular Pro.

There’s no big difference between the two other than the Pro model’s option to switch the outer shells. In addition, the Pro variant has a bigger battery and a physical button.

The Circular Ring is still new, but we were able to get our hands—er, finger—on it for a quick trial. So, for this review, we’ll be discussing first impressions, how the device looks and feels when you’re wearing it, how it works, and what we actually think about it.


Circular Ring Review
Circular Ring Slim (left) and Circular Ring Pro 1 (right) variants

Circular Ring Quick Summary

Before we start, here’s a quick summary of the Circular Ring’s functionalities:

Circular Ring Features
Heart tracking
Sleep tracking
Blood oxygen monitoring
Stress monitoring
Activity tracking
Menstrual cycle tracking
Physical button✅(Pro only)
Price$297 (Slim), $395 (Pro)

Circular Ring Review: First Impressions

First, let’s talk about the packaging. The Circular Ring comes in a cleanly designed box with an opening secured using a magnet. There’s not much to see outside the box, which means you’re actually encouraged to open it immediately to get the smart ring inside. Once you open the box, you’ll find the Circular Ring and its charger safely tucked in foam.

The Circular Ring looks simple and unassuming, but it feels premium. It’s very different from its predecessor in terms of appearance because first, there’s no physical rubber button that can be pushed; second, it has a matte finish different from the shiny finish on the Circular Pro’s outer shell; third, the Slim variant is noticeably slimmer; fourth, it has a simple but good-looking logo, which serves as the button; and lastly, its metal prongs that are used to charge the device are smaller compared to the ones found in Circular’s older smart ring.

As for the charger, there are two magnetic terminals that connect to the prongs on the smart rings. It has a USB-C connector, so you can connect it to your laptop, iPhone, or Android smartphone to charge the device. It also has an LED light that tells you if the ring is charging.


Using the Circular Ring Slim

Like the Circular Pro, the Circular Slim is used with a smartphone app. You will first need to download the app and then connect the Circular Slim to your smartphone using Bluetooth. You will also need to wear the smart ring to take advantage of all of its features, although some will still work while it’s not being worn.

First steps

To set it up, first charge your Circular Slim using the supplied charger. You can attach the charger to any device with a USB-C port, but this could be challenging if you are using your smartphone for the purpose, especially because you will need to use your smartphone in the succeeding steps. This will be easier if you have a USB-C cord extension, which you can also order from Circular.

Next, get the Circular Ring app for the iPhone or Android. Once you have it, you will need to Sign Up for an account with Circular if you don’t have one yet, or Sign In if you’re already have an account and/or are using a Circular Pro smart ring.


Once you’re already signed in, it’s time to connect the ring to the app. Tap on My Ring at the top-right corner of the screen, then tap on Set up new ring under General. From there, you will need to select Slim, then follow the slew of instructions that appear on the screen.

You might experience some connection issues, as we have. When you do, you might need to do a soft reset on the Circular Slim, remove it from the list of connected or recognized smart rings from the Circular app, and also forget the device in your smartphone’s Bluetooth settings. If you do this, simply connect the device to your smartphone as you did the first time.


What the Circular Slim Is Best Used For

If you succeed in connecting your Circular Slim to the app on your smartphone, congratulations! You are now on your way to enjoying its features, some of which can be compared to similar features on more expensive devices. We’ve tried it and can vouch for its effectiveness.

Health Monitoring

The Circular Slim smart ring is fitted with a slew of sensors used to measure your health statistics. The device accurately monitors your heart rate, HRV (heart rate variability), breathing rate, blood oxygen (SpO2), and the intensity of your current activity. Don’t worry about the information’s accuracy—the Circular app will give you tips on how to get these statistics best.

In our case, we were advised to clench our fists while the smart ring was measuring. The app showed that the data accuracy was “poor,” so we had to wait a bit longer for the data to become more accurate. Eventually, we decided to remove the Circular Slim, wait a few seconds, and then put it back on, but this time, it was in a relaxed position. The app indicated that the information is now more accurate, and we have confirmed it using other health monitoring devices. For reference, we wore the Slim on our right index finger.

Aside from the usual stats like heart rate, the Circular Ring also monitors your body temperature to help detect certain conditions, like a fever. It monitors your stats 24/7—as long as it has a battery—and gives you tips on how to improve your health.


On-Demand Measurement

While the Circular Ring monitors your health stats every minute, you have the option to get measurements on demand. This gives you instant access to the information you need at the time you need it, allowing you to stay on top of your health condition.

Monitoring and Handling Stress

The Circular Ring provides live stress score feedback and stress predictions based on the stats it measures while you engage in activities. It can then give you guided breathing exercises to help you relax, whether you’re still doing activities or are already preparing to sleep.

Improving Sleeping and Waking

Speaking of sleep, the Circular Ring is designed to help improve your sleep. It helps you ease into sleep by giving you notifications about your set bedtime. Then, it monitors your sleeping stages (REM, light sleep, deep sleep) and napping habits and provides tips on how they can be better. It also has a Smart Alarm feature that gently nudges you before your set alarm time so that you wake up gently and refreshed instead of abruptly due to strong vibrations.

Circular Ring Pro
Circular Ring Pro

Wellness Recommendations

Aside from the above, the Circular Ring also monitors your energy and provides you with helpful recommendations to improve your overall health and wellness. These include recommendations such as getting some sun, getting a cup of coffee, and working in what Circular calls your “Productivity Zone.” It also reminds you of your medications, if you have any, and alerts you if there’s anything wrong with your vitals.

Keeping track of time

While the Circular Ring is not a watch, you can use it to keep track of time. Simply set the alarm and Slim will vibrate at your specified time. This is perfect for instances when you aren’t wearing a watch and do not want loud noises to wake you up, like a blaring alarm from your phone. Use case scenarios include when you’re sleeping, driving, in a meeting, or in a noise-free zone.


Circular ring Pro - Circular Ring Review
Circular Ring Pro 1

Circular Ring Slim Pros and Cons

All that said, Circular Slim has some advantages and disadvantages. Here are some of the smart ring’s pros:

  • 2.2mm-thin profile and 2-gram weight make it very comfortable to wear
  • Aluminum build makes it durable
  • IPX8 rating lets you use it while swimming for 30 minutes

Now, some of its downsides:

  • You might forget you’re wearing it and end up doing something that can damage the ring
  • Matte finish scratches easily
  • You might forget that you’re not wearing it and end up having to reset it to reconnect
  • Disconnection issues can be very annoying
  • Slow to produce accurate measurements at times
  • Does not track workouts or exercise
  • No third-party integrations (does not work with Apple Health or Google Fit, and other apps)
  • Circular app could be better
  • Battery doesn’t last as long as Circular claims

The Verdict: Is Circular Ring Worth It?

Perhaps by now, it’s painfully obvious that the $297 Circular Slim looks and sounds good at first glance, but it’s not a powerhouse like other devices. It’s mainly used as a health tracker for everyday activities, a sleep tracker to help you get better sleep, and an alarm for when you want to wake up or be notified of certain times without any noise. It has some potential, as indicated on paper, but our user experience leaves a lot to be desired.

If you’re looking for a wearable that does these three things, don’t mind spending a week or so to let the device get acquainted with your habits, and don’t want to spend on more expensive but more powerful options, then Circular Slim might be good enough for your needs. But if you’re looking for something more reliable and do not mind spending more to get your money’s worth, get the Ultrahuman Ring Air, Oura Ring, or check out other smart rings.

Get the Circular Ring here!

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