After passing US$400,000 from 2,000 backers on its first day, the Japanese smart ring brand makes its international debut with a 5.19 mm-wide ring offering up to 10 days of battery life.
YOKOHAMA, Japan, Oct. 5, 2026 /PRNewswire/ -- SOXAI Inc. today announced that its SOXAI RING X smart ring has surpassed US$635,200 in pledges from 2,868 backers within 72 hours of its Kickstarter launch, after attracting 2,000 backers and more than US$400,000 in its first 24 hours.
With more than 80,000 users, SOXAI is Japan's No. 1 smart ring brand by cumulative app downloads[1]. SOXAI RING X marks the company's international debut, bringing together a width of just 5.19 mm—the narrowest in its category[2]—and up to 10 days of battery life[3].
Led by founder and CEO Dr. Tatsuhiko Watanabe, a former researcher at ETH Zurich, SOXAI develops its hardware, software and data analysis technologies together.
Proven Power Efficiency, Now in a Slimmer Ring
Low-power design is one of SOXAI's core engineering strengths. Its previous model, SOXAI RING 2, is already on the market and delivers up to 15 days of continuous use on a single charge—among the longest battery lives in the smart ring category.
SOXAI RING X builds on that experience, applying the company's expertise in power-efficient hardware and software to a more compact design. Users can review their sleep and activity in the companion app.
Original Engineering, Japanese Manufacturing
SOXAI RING X is an original product developed by SOXAI, not a rebranded white-label device.
SOXAI designs the ring's physical structure and functionality, developing its hardware, software and data analysis as a complete system. Manufacturing and testing are planned to take place in Japan, alongside ongoing data management and customer support.
A working prototype is already complete.
A Japanese Brand with a Focus on Sleep
Sleep has been central to SOXAI's product development. Japan's Ministry of Health, Labour and Welfare cites a 2021 survey in which Japan recorded the shortest average sleep duration among the 33 countries surveyed.
Joint research with the University of Tokyo and the University of Essex has examined sleep-stage estimation using heart rate and movement data from an earlier SOXAI RING model, with findings published in an academic journal. Studies of blood oxygen saturation (SpO2) measurement at rest and heart rate estimation during physical activity have also been published in academic journals.
These findings relate to earlier products and related technologies; they are not test results for SOXAI RING X.
From Japan to the World
The Kickstarter campaign is SOXAI's first step toward bringing its experience in Japanese product development and manufacturing to an international audience. Backer demand will help guide the company's rollout, including which countries and regions to prioritize.
Kickstarter Campaign Details
Project: SOXAI RING X: World's Smallest, Up to 10-Day Battery Campaign period: October 2, 2026, at 8:30 p.m. through October 10, 2026, at 11:59 p.m. Japan Standard Time (UTC+9). Project page: SOXAI RING X on Kickstarter
[1] Based on cumulative downloads of smart ring apps in Japan from January 2022 through December 2024, across the App Store and Google Play combined. Source: SOXAI research.
[2] Based on a comparison of ring widths publicly reported by major manufacturers of smart rings with vital-sign sensing capabilities. Source: SOXAI research, as of September 2026.
[3] Up to 10 days is a theoretical battery-life estimate for US ring sizes 10–13. Actual battery life varies depending on ring size, usage, product age and other factors.
SOXAI RING X is not a medical device and is not intended to diagnose, treat or prevent any disease. Countries and regions eligible for shipping and use will be determined based on applicable wireless regulatory certifications and other requirements.
About SOXAI
SOXAI Inc. is a smart ring company based in Yokohama, Japan, led by founder and CEO Dr. Tatsuhiko Watanabe. With more than 80,000 users, SOXAI combines expertise in low-power hardware design, software and data analysis to help people better understand their sleep, activity and everyday well-being.
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