For years, the smart ring has been pitched as a piece of jewelry that happens to read your sleep stages, your heart rate variability, and your blood oxygen. In reality, though, most smart rings are chunkier than anything you would pick at a jewelry store—something that many consumers find annoying.
Oura, the Finnish-founded, San Francisco-based company that helped invent the category over the past 12 years, has heard the complaint from its own customers repeatedly. “The feedback we always hear is, ‘We love the power and insights of the ring, but can you make it smaller?’” said Lindsey Belknap, Oura’s vice president of marketing. “We previously thought it would require compromising on functionality, features, and battery life but we’ve finally made some breakthroughs.”
Behind the scenes, wearable companies have been on a mission to cram a lot of technology—a battery, LEDs, infrared sensors, an accelerometer, a skin-temperature monitor—into increasingly thinner and more delicate rings.
Today, Oura is unveiling Oura Ring 5, a device roughly 40% smaller than its predecessor, with a uniform thickness of roughly 2 millimeters (0.8 inch) and a width that’s been shaved from about 8 mm to 6 mm. Crafted from scratch-resistant titanium, the ring is waterproof to a depth of 100 meters (328 feet). Preorders open today, with the ring shipping June 4. Pricing starts at $399 and runs to $499.
How Oura Ring scaled down
According to Belknap, the Oura team spent years working on the problem precisely because the obvious approach, shrinking existing parts, was a dead end. “In wearables, reducing size almost always forces you into a trade-off in battery life or accuracy,” she says. “It took us years to develop this ring because we had to rethink the mechanical and electrical architecture from the ground up.”
The answer came down to using fewer sensors rather than smaller ones. Oura Ring 5 has 12 sensing pathways, down from 18 in the previous generation, but Belknap says the remaining ones are more powerful and better positioned. The LEDs that pulse light through the skin to read blood-volume signals are now up to four times stronger than in previous generations, which matters because a thinner ring sits closer to the finger and has less room to capture a clean signal during high-motion activity like running or biking.
The battery, traditionally the bulkiest single component in any wearable, was redesigned entirely. The new architecture extends battery life to six to nine days —up from from five to eight days in the previous generation. Oura is also launching a separate, $99 size-matched wireless charging case that holds about a month of reserve power.
While Oura has been able to tap into new components that have hit the market over the past few years, many of the parts had to be custom built. “We’re often starting from scratch with partners and producers to make for us,” Belknap said. The aim, she said, is for the ring to feel “like jewelry first and technology second.”
The Battle of the Rings
Oura crossed $1 billion in revenue in 2025, growing 100% year over year, and is now valued at roughly $11 billion, making it the most valuable standalone wearable company in the world. It sells in more than 4,000 retail doors globally, including Walmart, Best Buy, Target, and Costco, and counts members in 150-plus countries.
That scale enables Oura to invest in research and development, and the Ring 5 launch is bundled with software updates that include a new health tracking system called Health Radar, GLP-1 medication tracking, live workout tracking, and a partnership with Counsel Health that puts a board-certified physician a tap away in the app.
Oura now sees the ring as an entry point to a personal health platform that encompasses lab work, clinical records, and continuous biometric data. The new finishes, like a warmer Deep Rose and a lighter true-gold tone, are designed to treat the rings as a fashion statement. Belknap says they are designed to “broaden appeal across genders and markets.”
But Oura also faces steep competition. The landscape includes Samsung’s Galaxy Ring, which unlike Oura charges no subscription and is positioned as a companion for Android users at $399; Ultrahuman’s Ring AIR at $349, which leans into the quantified-self and biohacking crowd; RingConn’s Gen 2 Air, which undercuts everyone at $199 and advertises a 10-day battery; and Amazfit’s $149 Helio Ring, positioned as a companion to its fitness watches. And while Oura is considered one of the best on the market, its $5.99 monthly membership is a persistent talking point among reviewers and buyers.
Against that backdrop, size begins to matter even more. It allows Oura to stand out from competitors that are slowly closing the software gap. Oura wants to create a ring that you forget you’re wearing.
A ring you forget you’re wearing is a ring you don’t take off—and a ring you don’t take off is one that keeps generating the kind of highly accurate longitudinal data that improves your health. “We’ve been working on creating a smaller, thinner ring with the same power for several years,” Belknap said. “So this has been a long time coming.”