Oura launches Ring 5, the world's smallest smart ring, with AI health monitoring and blood pressure signals ahead of $11bn IPO

Oura has officially launched the Ring 5, its fifth-generation smart ring, which the company claims is the smallest in the world. At 6.09mm wide and 2.28mm thick, the new device is 40% smaller than the Oura Ring 4, addressing a long-standing user request for a less conspicuous, more jewellery-like form factor. The ring weighs as little as 2 grams depending on size and is available for preorder immediately, with shipping beginning 4 June. Pricing starts at $399 for black and silver finishes, rising to $499 for gold, stealth, brushed silver, and a new deep rose colour. An Oura membership, required for full functionality, costs $5.99 per month or $69.99 per year.

Design and hardware refinements

Beyond the dramatic size reduction, the Ring 5 introduces several hardware improvements. The titanium exterior now features a physical vapour deposition (PVD) coating for enhanced scratch resistance, and the device is waterproof to 100 metres with an IP68 rating. Oura has redesigned the internal sensor array, using lower-profile sensor domes for better skin contact and LEDs that are four times more powerful than those in the Ring 4. The ring incorporates 12 independent signal pathways to improve accuracy across different finger shapes and skin tones. Battery life has been extended to between six and nine days per charge, up from the Ring 4's five-to-eight-day range. A new compact aluminium charging case, priced at $99, can provide five full charges — roughly an extra month of battery life — and is compatible with a new Locate feature for finding misplaced rings.

We have finally achieved what I think seems like a real technological miracle. This is what our members have been asking us for, for years.

AI-powered health monitoring

On the software side, Oura is positioning the Ring 5 as a proactive health platform. The headline addition is Health Radar, an upgrade to the Symptom Radar that debuted in 2024. This AI-powered system continuously tracks biometric signals — including body temperature, respiratory rate, and heart rate variability — in the background and surfaces alerts when it detects patterns suggesting strain. The most notable new feature is Blood Pressure Signals, which detects shifts and patterns that may indicate cardiovascular strain. Oura stresses that the ring does not measure blood pressure directly; instead, it tracks biometric patterns that correlate with rising blood pressure and alerts users to concerning trends. A Nighttime Breathing feature provides a 30-day rolling view of sleep-related breathing patterns and disturbances, using LED sensors to track significant shifts in blood oxygen levels during sleep, which could prompt conversations with a doctor about conditions like sleep apnoea.

The [Ring 5] is the most capable wearable we've ever made - small enough to fit seamlessly into everyday life, and significant enough to set a new standard.

Fitness and lifestyle features

The Ring 5 introduces live workout tracking, allowing users to start a workout in the Oura app and see second-by-second tracking of pace and distance — though they must still pull out their phone mid-run to view the data. Oura is also adding GLP-1 insights, a feature that tracks weight and body changes for members taking GLP-1 medications like Ozempic and Wegovy. The Oura Advisor, an AI health coach, is part of the company's broader push into AI-powered wellness insights, similar to how Google is positioning its AI Health Coach within the redesigned Google Health app.

Market context and IPO ambitions

Founded in 2013 in Oulu, Finland, by former Nokia and Polar engineers Petteri Lahtela, Markku Koskela, and Kari Kivela, Oura has sold 5.5 million rings across four generations in 150 countries since its first Kickstarter campaign in 2015 raised over $650,000. The company now has about 5 million paying subscribers and reported $1 billion in revenue in 2025, representing fourfold growth over two years. Valued at $11 billion, Oura is preparing for a US IPO expected later this year. The smart ring market saw 4 million devices shipped in 2025, more than doubling in each of the past two years, though it remains a fraction of the 175 million smartwatches shipped in the same period. The Ring 5 launch comes amid growing competition, notably from Google's recently launched Fitbit Air, as demand for passive, screenless fitness trackers continues to heat up.