Circular Ring 2 review: I wanted to love it, but the software got in the way | Tech Radar

Overview

News, deals, reviews, guides and more on the newest computing gadgets

Start exploring exclusive deals, expert advice and more

Details

Unlock and manage exclusive Techradar member rewards.

I tested the Circular Ring 2 and wanted to love it, but the software got in the way

Circular still hasn't fixed its biggest weakness

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

At first glance, the Circular Ring 2 looks like a serious smart ring contender. It’s got impressive health features, feels comfortable to wear and avoids the subscription fees charged by some competitors. Unfortunately, the experience is undermined by unreliable syncing, unfinished features and an app that’s confusing to navigate. The most frustrating part is that many of these issues were present on the previous model. Circular has improved the hardware, but the software still isn't good enough to compete with the best smart rings available today.

Best smart ring 2026: The top discreet fitness trackers

The best Fitbit 2026: Band-style fitness trackers and Google smartwatches

We spend hours testing every product or service we review, so you can be sure you're buying the best. Find out more about how we test.

The Circular Ring 2 is an ambitious smart ring. On paper, it has almost everything you need. Alongside standard health, recovery and sleep tracking, it offers features you won't find on many rivals, including electrocardiogram (ECG) readings and atrial fibrillation (AFib) detection. Circular is also promising blood pressure and blood glucose trend monitoring in future updates.

At first glance, it feels like a genuine challenger to the likes of Oura, Ring Conn and Samsung. The ring itself looks good, feels lightweight on the finger and comes with a charging case, which is a welcome upgrade over the previous Circular model. Battery life is solid too, lasting around six days during my testing.

But unfortunately, the day-to-day experience doesn't live up to that impressive spec sheet.

The biggest issue is the software. Smart rings don't have screens, which means the app is incredibly important. That's where the Circular Ring 2 struggles the most.

Syncing regularly took several minutes, occasionally failed altogether and often required multiple attempts. Several times I opened the app to check my data, waited for it to sync, gave up and closed it again.

The app itself feels cluttered and unintuitive. Health data is scattered across multiple screens, navigation can be confusing and the language often feels strangely robotic.

One morning, for example, I was told my sleep was "Incorrect" and the next my wellness summary informed me: "Your sleep was correct. Your energy seems low. Your body and mind are unbalanced." Rather than helping me understand my health, experiences like this often left me more confused.

Some of the ring's most exciting features also failed to impress. ECG and AFib monitoring never fully worked during my testing, while promised blood pressure and glucose tracking features have yet to arrive.

What makes all of this especially frustrating is that when I revisited my Circular Ring Slim review from back in 2024, I found many of the same complaints. The hardware has definitely improved, but the software experience still feels a step behind the competition.

The Circular Ring 2 isn't a bad smart ring. It has a good design, respectable battery life and an ambitious feature set. But in a market increasingly dominated by the best smart rings from polished competitors like Oura, Ring Conn and Samsung, ambition alone isn't enough. Right now, Circular still feels like a company with great ideas struggling to execute them.

£280 (black), £360 (silver), £440 (rose gold, gold) /

£280 (black), £360 (silver), £440 (rose gold, gold) /

Titanium body, hypoallergenic interior with a PVD coating

Titanium body, hypoallergenic interior with a PVD coating

Up to 8 days (power mode); 5 days (performance mode)

Up to 8 days (power mode); 5 days (performance mode)

Rolled out after a Kickstarter release in late 2025 / early 2026

No subscription needed, but premium features expected soon

Rather than arriving as a traditional retail release, the Circular Ring 2 began life as a Kickstarter project in 2025 before gradually rolling out to customers through late 2025 and into 2026.

Pricing starts at £280 /

At first glance, the Circular Ring 2 looks competitively priced. One of its biggest selling points is that it doesn't require a mandatory subscription to access core features, unlike the Oura Ring 4, which starts at £349 /

However, the picture becomes a little more complicated when you look closer. Circular is already promoting upcoming premium features, including blood pressure and blood glucose trend monitoring, which aren't available but are expected soon. The company says these features will either require a subscription or can be unlocked using Circular Coins, which are earned through regular use, but details remain limited and pricing has yet to be confirmed.

Looking across the wider smart ring market, the Circular Ring 2 sits in a crowded middle ground. It's cheaper than the Samsung Galaxy Ring, which starts at £399 /

The problem isn't necessarily the asking price here but more that the performance doesn't justify it. While the Circular Ring 2 undercuts some of the biggest names in the category, like Oura, Samsung and Ring Conn, they all currently offer a more polished experience. That makes the Circular Ring 2 difficult to view as good value, even before any future premium features are brought into the equation.

I liked the design of the Circular Ring 2. The fit was very comfortable throughout testing, even when I was sleeping, and at just 2g it felt light on my finger. The silver finish also looks fairly premium.

Circular offers a wide range of sizes here, from 6 to 14, which beats most rivals. I tested a size 8 on my left index finger, which matched the recommendation from Circular's new digital AI sizing tool.

While the company still offers a traditional sizing kit as well, it's nice to see a less wasteful digital alternative that actually proved accurate in my case. Especially considering you’ll need to pay an extra £5 / $5 for Circular's traditional sizing kit.

The Circular Ring 2 has softer, more rounded edges than rivals like the Ring Conn Gen 2 or previous Circular Ring Slim. Whether that's a positive or negative will come down to personal preference, but it does make the ring feel slightly chunkier than some competitors despite it being one of the slimmest choices available at 2.5mm thick. A small circular logo on the outer edge makes it easy to get the right way round so that the sensors are where they need to be.

I tested the silver model, which I'd recommend over the black version. Black smart rings tend to show scratches more easily, and that was one of the big problems on the previous Circular Ring Slim. After two weeks of wear, my ring had picked up a few minor scuffs but was in good condition overall.

Another welcome improvement here is the charging case. Unlike the Circular Ring Slim, which relied on a charging cable and small plinth, the Ring 2 ships with a compact clamshell charging case that's easy to carry and use.

Overall, the ring's design is one of the Circular Ring 2's biggest strengths. The company has clearly refined the hardware. Unfortunately, as we'll see later, the software hasn't evolved at the same pace.

The Circular Ring 2 has an ambitious set of features. Alongside standard health, sleep and activity tracking, it measures metrics like heart rate, heart rate variability (HRV), blood oxygen saturation (Sp O2), skin temperature and breathing rate.

There are also women's health features designed to track hormonal shifts and fertility, plus stress monitoring, guided breathing exercises, medication reminders and an AI assistant called Kira.

The headline features are ECG measurements and AFib detection, both of which are rare in smart rings. Circular is also promising blood pressure and blood glucose trend monitoring in future updates, though neither feature was available during testing and both will sit behind a premium-ish model when they arrive. Blood pressure is not easy to measure with LED-based optical heart rate sensors, without an inflatable cuff for calibration: it will be interesting to see what form the blood pressure feature eventually takes, and whether it will be accurate.

On paper, it's an impressive package that rivals, and in some cases actually exceeds, what you'll find from bigger names in this space.

The Circular Ring 2 made a good first impression. Basic metrics like steps, heart rate and sleep tracking all seemed reasonable during the first few days of testing. But the longer I wore it, the more problems started to emerge.

The biggest issue is the app. Smart rings don't have screens, which means if you think about it, the app effectively is the product, much like a Whoop band. That's where the Circular Ring 2 falls behind rivals.

Syncing is frustratingly slow. Pulling data from the ring often took several minutes and occasionally failed altogether, forcing me to try again. That might sound like a small complaint, but it adds unnecessary friction. Several times I found myself opening the app, waiting for data to sync, then simply closing it again. If I owned this ring long-term, I suspect I'd eventually stop checking the app altogether.

The app itself feels cluttered and unintuitive. Health insights, scores, charts and features are scattered across multiple screens, while the home page is filled with circles, cards and widgets competing for attention. Even as someone who tests wearables for a living, I often found it harder than it should be to locate specific information.

The language doesn't help either. As mentioned above, the app kept telling me my sleep was “Incorrect”, or my body was "unbalanced", which left me confused rather than enlightened.

The AI assistant, Kira, wasn't much better, largely repackaging existing data in a confusing format with tiny fonts and a huge chunk of text with generic recommendations, like "stay hydrated". Some of the ring's most exciting features also failed to deliver. ECG and AFib monitoring never fully worked during my testing, repeatedly getting stuck on a loading screen.

Sleep tracking was generally accurate when I followed a conventional sleep schedule, but it struggled with fragmented sleep and occasionally recorded inaccurate sleep times. On several occasions I woke up for a few hours before going back to sleep, only for the ring to record the entire period as one continuous sleep session.

Workout tracking isn’t what smart rings do best. But here it still feels like an afterthought. Sports Sessions are hidden away, must be started manually and there's no automatic workout detection, unlike competitors like the Oura Ring 4 and Samsung Galaxy Ring. I also experienced a handful of smaller bugs, including random disconnections and occasional time zone changes despite not travelling anywhere.

Battery life is one area where the Circular Ring 2 performs well. Circular promises up to five days in Performance Mode and I managed six days during testing. That's competitive with most major rivals and a significant improvement over the Circular Ring Slim.

Overall, the Circular Ring 2 feels like a smart ring with excellent ideas but inconsistent execution. Yes, the hardware is good, the feature list is impressive and the battery life is solid. But the software experience remains frustratingly rough around the edges, and in an increasingly competitive smart ring market, that's difficult to overlook.

There’s no subscription, which makes it seem like good value. But once you factor in the inconsistent performance and the strength of the competition, it's difficult to justify the price.

There’s no subscription, which makes it seem like good value. But once you factor in the inconsistent performance and the strength of the competition, it's difficult to justify the price.

Lightweight, comfortable to wear and I liked the charging case. It doesn't stand out against the best-looking smart rings on the market, but the hardware feels thoughtfully designed with minimal signs of wear.

Lightweight, comfortable to wear and I liked the charging case. It doesn't stand out against the best-looking smart rings on the market, but the hardware feels thoughtfully designed with minimal signs of wear.

An impressive range of health, wellness and sleep tracking features, including ECG and AFib monitoring. The challenge isn't the breadth of features available, but the fact that some are still missing despite being promised.

An impressive range of health, wellness and sleep tracking features, including ECG and AFib monitoring. The challenge isn't the breadth of features available, but the fact that some are still missing despite being promised.

The feature set is promising, but it’s held back by slow syncing, buggy behavior and an app that feels cluttered and unfinished. Battery life is good, but an overall lack of polish makes it difficult to recommend.

The feature set is promising, but it’s held back by slow syncing, buggy behavior and an app that feels cluttered and unfinished. Battery life is good, but an overall lack of polish makes it difficult to recommend.

You don't want to pay a subscription Most of its features are available without an ongoing monthly fee. If you've been put off smart rings like Oura because of the subscription, this is a big draw.

You want a comfortable smart ring It’s lightweight, comfortable to wear and a noticeable improvement over the Ring Slim that came before it.

You mainly want general health insights If you're looking for a broad overview of things like sleep, recovery and activity rather than detailed fitness data, it does cover the basics.

You want a polished, reliable experience Slow syncing, occasional bugs and an unintuitive app make the Circular Ring 2 feel less refined than leading rivals.

You care about data accuracy Sleep tracking struggled with fragmented sleep during testing, ECG and AFib monitoring didn't work consistently, and workout tracking feels underdeveloped.

You're considering Oura, Samsung or Ring Conn The Circular Ring 2 has an ambitious feature set, but the overall experience isn't as polished as the leading smart rings on the market.

For a more premium and polished ring, app and performance, try the Oura Ring 4. The main reason I'd dissuade people from the Oura is it's expensive, but the silver version is actually cheaper than the Circular Ring 2. Granted you do then have to pay £5.99 / $5.99 per month for the subscription, but that's still better value considering it's a major step up in performance. The Oura Ring 5 has just been released, which means if you want the cream of the crop do consider that too.

Now, this ring is not necessarily better than the Circular Ring 2. It certainly doesn't track as much, the design isn't as premium-looking and there are limited sizes. But I'm including it for those on a budget, as it's significantly cheaper and continues to be reduced. On the Amazfit site at the time of writing, you can pick one up for £149.90 / $149.99. Ideal if you're not sure if the smart ring form factor is for you.

I tested the Circular Ring 2 for 2 weeks. I wore it 24/7 and only took it off to charge it and when I was lifting weights — I learned the hard way testing smart rings over the years that they're very easy to scratch. It was on throughout workouts, working, socializing, relaxing on an evening and sleeping at night.

I've been reviewing smart rings since the very first iteration of the Oura ring came out in 2017 and have tested almost every generation from every smart ring brand since. Which puts me in a great position to compare models, tell you which is right for you and bring you that all important context about the smart ring industry.

Becca is a contributor to Tech Radar, a freelance journalist and author. She’s been writing about consumer tech and popular science for more than ten years, covering all kinds of topics, including why robots have eyes and whether we’ll experience the overview effect one day. She’s particularly interested in VR/AR, wearables, digital health, space tech and chatting to experts and academics about the future. She’s contributed to Tech Radar, T3, Wired, New Scientist, The Guardian, Inverse and many more. Her first book, Screen Time, came out in January 2021 with Bonnier Books. She loves science-fiction, brutalist architecture, and spending too much time floating through space in virtual reality.

You must confirm your public display name before commenting

1'We've seen an increase in Blu-ray orders of 10,000%': I spoke to a Blu-ray and vinyl manufacturer about their Blu-ray sales and it's given me even more hope for physical media's survival

2I found a hidden Chat GPT setting that changes how hard the AI thinks — and the difference surprised me

3 This tiny AMD PC just ran a massive 397B AI Model that required a server room full of GPUs a year ago

4100 days after the Iran war started — Tehran-backed group breaches California Water Service but claims they 'chose not to disrupt water access'

5 The US almost blacklisted Deep Seek for contributing to China’s military and intelligence — but the White House held back to avoid escalating tensions

Tech Radar is part of Future US Inc, an international media group and leading digital publisher. Visit our corporate site.

© Future US, Inc. Full 7th Floor, 130 West 42nd Street, New York, NY 10036.

Key Takeaways

• News, deals, reviews, guides and more on the newest computing gadgets

• Start exploring exclusive deals, expert advice and more

• Unlock and manage exclusive Techradar member rewards

• I tested the Circular Ring 2 and wanted to love it, but the software got in the way

• Circular still hasn't fixed its biggest weakness