Luna Ring Gen 2 review: A stylish and subscription-free smart ring

Price When Reviewed

From $269

Best Prices Today: Luna Ring Gen 2

The Luna Ring Gen 2 is another subscription-free smart ring that wants to eat into the sales of the Oura Ring 4 and Samsung Galaxy Ring.

India-based Noise’s second-generation Luna turns to AI in an attempt to stand out from the growing number of connected rings. It uses machine learning to offer advice on workouts and help you make better nutrition decisions.

While the number of smart rings available is still relatively small, there are already some strong subscription-free options out there. Does the Luna Ring Gen 2 make a strong enough case to be another one you should put on your finger?

Here’s how things played out when I slipped on the Luna Ring Gen 2.

Design & Build

• Available in five colour finishes
• Comes with portable charging case or a dock
• Waterproof up to 50 metres

The Luna Ring Gen 2 has similar design traits to many other smart rings. It’s made mainly from titanium, with a non-allergenic moulding on the inside where you’ll find the all-important sensor bump.

The sensor array, while not uncomfortable, did sit snug on the underside of my finger.

There are five colour options to choose from – Stardust Silver, Lunar Black, Sunlit Gold, Midnight Black and Rose Gold. The version I tested is the Sunlight Gold model, which has picked up a few little scratches during testing. The ripple effect on the titanium helps to give it a distinctive look to help set it apart from other smart rings.

If you’re unsure of fit, there’s a free sizing kit available. I’ve found sticking to the same size as other smart rings has got me a good fit overall.

How you choose to charge the Luna Ring will impact on how much you pay for the ring overall. The pricier option is to grab it with the pretty portable charging case (pictured). You can also opt for the dock charger to save some money (detailed pricing is below).

If you want to take it for a swim, the 5ATM rated design means it can survive submerged in water up to 50 metres depth. I’ve worn it in the shower, in the pool and even in heavy downpours and the Luna has survived all of those scenarios.

Fitness & Tracking

• Tracks step, sleep, heart rate and stress
• Free Luna app available for iOS and Android
• LifeOS insights and guidance

There are some pretty standard smart ring sensors in play here that take care of monitoring your data. That includes continuously keeping tabs on heart rate and daily step counts.

A green optical sensor is present to cover heart rate tracking, a red one for blood oxygen monitoring and there’s also room for a skin temperature sensor. Movement tracking is covered by a 3-axis accelerometer.

Data is stored in the Luna app, which has a nice, stylised interface, breaking down daily totals, sleep, readiness scores, activity tracking and the Luna AI features. 

For sleep, I’ve been wearing it alongside the Oura Ring 4 and data like sleep duration and period of sleep as well as deep and REM sleep stages were pretty similar. In addition to those core sleep stats, you can also see trends on hitting recommended sleep goals, whether you’re hitting sufficient restorative sleep and these are all cleanly explained in the app.

Next up is Readiness, which is a metric other rings have also adopted. This looks at metrics like heart rate, respiratory rate and temperature. Again, Readiness scores were surprisingly similar to those captured by an Oura Ring 4.

There are some nicely presented summaries of that readiness data to help you better understand what your scores are telling you. I will say, though, that heart rate readings in general were a bit on the generous side. This isn’t the most accurate smart ring for tracking heart rate.

Next up is activity tracking, where you’ll be able to see daily step totals, distance covered, calories burned, along with displaying contributing factors to your overall activity score. The daily step totals didn’t look wildly out from other fitness trackers.

If you want to track a workout, you can do that manually. Runners and keen walkers also benefit from automatic workout recognition, which has worked pretty reliably in my testing.

Then there is Luna AI, which you can view as your hub to learn more about the metrics this ring can track, as well as setting up workout and diet plans. There’s also a daily digest feature, which neatly outlines some of your key data points and what they’re telling you. Generating workout and diet plans is very ChatGPT in approach and right now, it doesn’t feel hugely personalised or compelling to use.

Battery Life & Charging

• Up to 5 days battery life
• Charging case offers 30 days battery
• Fully charges in 120 minutes

I’ve managed to get roughly 5-6 days of battery life out of the Luna Ring on a single charge.

That’s what’s quoted by Noise, so it does at least meet those claims. That’s still short of the battery life you will get from the Oura Ring 4, Samsung Galaxy Ring and RingConn Gen 2. You’ll see notifications from the app when it gets low to make sure you don’t get caught short on battery.

The portable ‘Surge Charge’ case has a sizable 500mAh capacity battery. When full, it will give you enough battery to power up for 30 days. When it does get low, I’ve found it takes roughly an hour to get from 0-100%, which is a charging rate largely in keeping with the competition.

Price & Availability

The Luna Ring Gen 2 launched in July 2025, priced from £269/$300. That makes it cheaper than the Oura Ring 4, where pricing starts at £349/$349 and goes a lot higher for certain models.

As mentioned earlier, that starting price will just get you the standard charging dock, or you can spend £299/$329 for the portable charging case, which is a small price to pay for the added convenience.

Though there are prices available in dollars, the official store says the Luna Ring Gen 2 isn’t available in the USA.

Unlike Oura, there’s no additional monthly or annual fee to pay to use all of the available features. That means it joins the likes of the Samsung Galaxy Ring ($399.99), the Ultrahuman Ring Air ($349), Circular Ring 2 (from $349) and the RingConn Gen 2 ($299) as rings where you just need to pay for the hardware alone.

Check out our list of the best smart rings you can buy right now.

Should you buy the Luna Ring Gen 2?

I think there’s a fair amount to like about the Luna Ring Gen 2 and what it offers as a smart ring. The design is nice, the app is pretty slick if a little busy, and most of the tracking is solid overall.

I do think it’s let down in a couple of key areas. Most notably with the heart rate tracking and a battery life that’s not quite up there with the competition. There’s plenty to work with here and I do think if you value features like sleep tracking and giving your data context, the Luna Ring Gen 2 does a good job of that.

It was a smart move to price it below the competition, though, as it doesn’t compete well enough in all areas to beat the best in the category.

Specs

• Up to 5 days battery life
• Optional portable charging case
• Works with Android and iOS
• Subscription-free
• Weighs 3-5g (depending on size)
• Waterproof up to 50 metres
• Optical heart rate sensor
• Optical blood oxygen sensor
• Skin temperature sensor