ŌURA Announces the World's Smallest Smart Ring, 'Oura Ring 5'

ŌURA, a world-leading smart ring manufacturer (CEO: Tom Hale), today announced the launch of the 'Oura Ring 5' in Japan. The product will be available for purchase starting at 12:00 AM on Friday, June 5, 2026.

Built on over 12 years of industry-leading innovation, Oura provides the most advanced health sensing and insights in a more comfortable and compact form factor than ever before. Crafted from lightweight, hypoallergenic titanium, the 'Oura Ring 5' goes beyond mere tracking, combining the most innovative hardware yet with new software that delivers deeper, more actionable insights, bringing a remarkable new experience to women's health and activity.

*World's smallest: Based on internal research as of March 2026 (comparing with the smallest sized products from over 200 major brands).
40% smaller than previous model: Based on volume comparison with Oura Ring 4.

For over a decade, Oura has demonstrated that the finger is the optimal site for measuring health data, playing a critical role in establishing the smart ring category.

Because finger arteries can deliver pulse signals to optical sensors up to 100 times stronger and clearer than those measured at the wrist, it is possible to acquire highly accurate biometric data such as heart rate and sleep metrics. As a result, Oura has built a foundation for achieving more accurate and reliable measurements than wrist-worn devices like smartwatches.

■ Redesigned Sensing

Oura introduces the 'Oura Ring 5,' which is 40% smaller than the 'Oura Ring 4,' making it the world's smallest smart ring. By redesigning the mechanical, electrical, optical, battery, and sensing architecture, Oura has achieved its most refined silhouette to date.
Designed to be thinner, lighter, and to fit perfectly and naturally on the finger, it features smooth curves. This change in size makes the Oura Ring even more attractive to a wider audience, especially for those seeking a truly discreet form factor.

The new signal architecture combines a precision-engineered low-profile sensor dome for better skin contact, high-output LEDs for clearer and more stable measurements, and 12 enhanced signal pathways. This enables higher measurement accuracy across all finger types and skin tones.

■ Sophisticated New Design and Oura's Highest Level of Durability

'Oura Ring 5' features a timeless design and is available in sizes 6 through 13. Two new colors have been added: 'Gold,' a bright and modern shade close to real gold, and 'Deep Rose,' a deep copper-rose tone.

Furthermore, it is the most scratch-resistant model in Oura's history, designed for wear in every daily scenario.
In addition to improved scratch resistance via a newly adopted high-durability PVD coating*2, it is equipped with 100m water resistance (IP68 standard*3) and dust-proof performance, allowing it to be worn comfortably during workouts, travel, and rest.

*2 An advanced surface treatment technology that forms an extremely thin and strong film on the product surface by vaporizing metal particles in a vacuum. It excels in wear and scratch resistance, protecting the ring's beauty from daily friction and impact.
*3 The highest rank of dust and water resistance defined by international standards. It shows high protective performance against dust and use underwater (Oura Ring 5 is designed for 100m water resistance).