I just went hands-on with the new Circular Ring 2 — and it's the most impressive smart ring at CES 2025

The new Circular Ring 2 smart ring shown at CES 2025 in the Circular booth
(Image credit: Dan Bacaglia/Tom's Guide)

I checked out a lot of smart rings at CES 2025. Highlights include the new Ultrahuman Rare collection, the latest RingConn Gen 2 wearable, the Luna Ring 2 from Noise and the new VIV Ring, a smart wearable that generates personalized audio to help users sleep better.

Those devices all intrigued me — and I look forward to more hands-on time with each — but the most impressive smart ring at CES 2025 has to be the Circular Ring 2.

Chosen as one of our top 25 best products of CES, I was fortunate enough to get some serious hands-on time with the new device. I also got to test out the potentially ground-breaking new digital sizing tool, which generates measurements for all of your fingers in a matter of seconds; no plastic sizing kit needed.

With holistic tech and wellness insights similar to Oura and Samsung and no subscription fees to speak of, here are my first impressions of the new Circular Ring 2.

Circular Ring 2: Pricing and availability

The new Circular Ring 2 smart ring shown at CES 2025 in the Circular booth

(Image credit: Dan Bacaglia/Tom's Guide)

Available in four finishes, including gold, rose gold, silver and black, the Circular Ring 2 starts at $349. That’s the same starting price as the Oura Ring 4 but unlike Oura, Circular doesn’t require a $5.99 monthly subscription.

The Circular Ring 2 also starts at $50 cheaper than the Samsung Galaxy Ring which is also subscription-free. However, Samsung’s wearable is Android only. Presale for the Circular Ring 2 will launch later this month, initially via Kickstarter, with units expected to ship in March.

Circular Ring 2: Digital at-home sizing feature

A demo of the Circular Ring 2's digital sizing feature with a user pointing a smartphone camera at their hand next to a credit card-sized piece of plastic

(Image credit: Dan Bacaglia/Tom's Guide)

Perhaps the biggest thing holding back smart rings in 2025 is the down-right antiquated sizing process that most major device makers force upon users before making their purchase.

Oura and Samsung both charge you $10 to have a box of plastic dummy rings in all the various sizes mailed to your home. Once you’ve confirmed your size, the kit is bound for the trash heap.

Circular has a better way. The brand’s new digital sizing tool requires nothing more than your smartphone camera, your hand and a credit card (or something that size, like a hotel room key). I tried it on the show floor and it worked remarkably well. With your hand and credit card in the frame, you simply snap a photo and let the tool do some AI churning.

Circular Ring 2 Beats Oura With NO Subscription! - YouTube Circular Ring 2 Beats Oura With NO Subscription! - YouTube
Watch On

A few moments later, you’re measurements are ready. For each finger, the two closest sizes are provided along with a chart showing where exactly your measurement lies between the two.

For example, my index finger was smack in between a size 11 and 12. However, my ring finger was almost an exact size 11. So, if I were shopping for a Circular Ring, I’d likely opt for the 11 and wear it on my ring finger rather than go with the 12 and risk it being a tad loose on my index.

The Circular Ring 2 will be available in sizes six through 13.

A display at CES 2025 showing all the sizes of the new Circular Ring 2 smart ring, including 6-13

(Image credit: Dan Bacaglia/Tom's Guide)

Circular Ring 2: Design and build-quality

The Circular Ring 2 received a major design overhaul compared to the original Circular Ring. Now a fully enclosed loop, the exterior of the Ring 2 is entirely titanium, rather than a mix of materials, which should result in greater overhaul durability and fewer scratches.

On my finger, it felt lightweight and quite comfortable. This is despite several sensors protruding out slightly from the inside of the band. Of the four finishes available, the jet-black variant was my favorite, though the classic gold was a close second.

Battery life is rated at six days, a bit less than the best smart rings we’ve tested but still a respectable amount of longevity.

The new Circular Ring 2 smart ring shown at CES 2025 in the Circular booth

(Image credit: Dan Bacaglia/Tom's Guide)

Circular Ring 2: Onboard ECG with AFib detection

The Circular Ring 2 is one of the first smart rings with onboard ECG readings, a feature found on most of the best smartwatch models but absent on the latest Oura Ring 4 and Samsung Galaxy Ring. The tech is even FDA-cleared to monitor for irregular heartbeats that could indicate Atrial fibrillation (AFib), a potentially deadly condition.

While I didn’t get to test the feature, as noted above, I did get to try on the Circular Ring 2 to get a sense of its durability and comfort. Like most modern smart rings, it’s lightweight and fairly unobtrusive, two things I prize in a wearable that’s designed for sleep tracking/intended to be worn to bed.

Circular Ring 2: Sleep tracking and energy insights

Sleep data from the Circular Ring 2 smart ring is shown in the device's companion app with a chart displaying sleep stages

(Image credit: Dan Bracaglia/Tom's Guide)

The device’s daily sleep reports look impressive. In addition to a sleep score from 1-100, users can view their various sleep stages, sleep duration, heart rate variability, fall-asleep and wake-up times. You can also see any sleep disturbances that may have impacted your rest.

While not quite as detailed as Samsung’s sleep data, which I'm more familiar with than Oura's, the information is presented in an easy-to-parse manner with color-coated graphics.

Similar to Oura’s Readiness Score and Samsung’s Energy Score, Circular also generates a daily Energy Score for users based on both rest quality and physical activity.

Circular Ring 2: Future outlook

The Circular Ring 2, up close, with half of the device slightly obstructed by orange glass in the foreground

(Image credit: Circular)

2024 was supposed to be the year of the smart ring and though we saw several notable new releases, not just from Samsung and Oura but Amazfit too, it's not as if every other person at the local Starbucks is suddenly wearing smart rings like they are smartwatches.

By removing hurdles from the sizing process — Circular Ring 2 customers will be able to access the digital sizing tool when purchasing the ring — and maintaining a subscription-free model with an app that plays nicely with both Android and iOS, the Circular Ring 2 could be the smart ring that cracks the mass adoption code in 2025.

Of course, the device's wellness tech and new heart-monitoring tools will need to prove accurate and reliable. Circular is also overhauling the companion app, which, likewise, will need to come close to, if not match the level of holistic insight and detail offered by Oura and Samsung, to be a serious competitor.

I'll hold off making any concrete judgments until I've had the chance to get the new Circular Ring 2 in and spend some serious one-on-one time with it. Look out for a full review in the coming months. In the meantime, what are your thoughts on the Circular Ring 2? Do you think it can compete with other brands in the space and would you buy one? Let me know in the comments below.

More from Tom's Guide:

TOPICS
Dan Bracaglia
Senior Writer, Fitness & Wearables

Dan Bracaglia is the Tom’s Guide editorial lead for all things smartwatches, fitness trackers and outdoor gear. With 15 years of experience as a consumer technology journalist testing everything from Oura Rings to instant cameras, Dan is deeply passionate about helping readers save money and make informed purchasing decisions. In the past year alone, Dan has assessed major product releases from the likes of Apple, Garmin, Google, Samsung, Polar and many others. 

An avid outdoor adventurer, Dan is based in the U.S. Pacific Northwest where he takes advantage of the beautiful surroundings every chance he gets. A lover of kayaking, hiking, swimming, biking, snowboarding and exploring, he also makes every effort to combine his day job with his passions. When not assessing the sleep tracking and heart rate accuracy of the latest tach gadgets, you can find him photographing Seattle’s vibrant underground music community.

Read more
The Circular Ring 2, up close, with half of the device slightly obstructed by orange glass in the foreground
The Circular Ring 2 is here and it beats the Oura Ring in two big ways
Hands-on with the RingConn Gen 2 smart ring
I just went hands-on with RingConn Gen 2 — a subscription-free alternative to Oura Ring promising 150-plus days of battery
Hands-on with the Luna Ring 2 smart ring shown up-close in a user's palm
I just went hands-on with the Luna Ring 2 — the Oura Ring alternative that promises way more battery life
The Circular Ring 2, up close, with half of the device slightly obstructed by orange glass in the foreground
Circular Ring 2 is now available to pre-order — and you could save up to $310 right now
A giant CES show banner hanging above an escalator at CES 2025 with people milling about
My 7 favorite wearables of CES 2025 — from a smarter smart ring to electric-powered pants
Person holding the Samsung Galaxy Ring in silver and gold
Best Oura Ring alternatives 2025
Latest in Fitness Trackers
The Circular Ring 2, up close, with half of the device slightly obstructed by orange glass in the foreground
Circular Ring 2 is now available to pre-order — and you could save up to $310 right now
Garmin golf watch
I played a golf round with the Garmin Approach S50 smartwatch, and it's fantastic — here's why
Oura Ring 4 in Rose Gold held between a person's fingers
Oura Ring just got a huge new upgrade for women's health — what you need to know
Close up of the Amazfit Active 2 smartwatch next to the Fitbit Sense 2 with each showing the total step count for the day
I walked 6,000 steps with Fitbit Sense 2 vs Amazfit Active 2 — this one was more accurate
Close-up of the Amazfit Active 2 and Apple Watch SE next to each other on a user's wrist
I walked 7,000 steps with Apple Watch SE vs Amazfit Active 2 — here's the winner
Fitbit Charge 6 shown on man's wrist
Epic Fitbit sale at Amazon — our favorite fitness trackers are on sale from just $79
Latest in News
Simone Ashley and Hero Fiennes Tiffin in "Picture This" now streaming on Prime Video
Prime Video top 10 has 3 must-watch movies — including a bubbly romcom starring 'Bridgerton's' Simone Ashley
(L-R) Josh Hartnett as Cooper and Ariel Donoghue as Riley in "Trap"
Netflix top 10 movies — here’s the 3 worth watching right now
iOS 19 logo on an iPhone
Apple WWDC 2025: iOS 19 and everything we know so far
Siri
Siri 2.0 features reportedly only working ‘two-thirds to 80% of the time’
Jack Draper in action at Indian Wells 2025
How to watch Indian Wells men’s and women’s finals: live stream tennis online
NYTimes Connections
NYT Connections today hints and answers — Sunday, March 16 (#644)