Casio’s original ring watch was a delightful bit of nostalgia-fuelled miniaturization — a functioning timepiece shrunk down to fit on a finger. The new CRW-H001M-8 looks almost identical, but under that familiar shell it has grown up into a genuine health tracker.
The transformation is more substantial than the outward resemblance suggests. Where the first model was essentially a tiny watch you wore as jewellery, this one packs a suite of sensors that put it firmly in smart-ring territory. It tracks heart rate, blood oxygen, sleep and body temperature, and it doesn’t just take spot readings — heart rate, blood oxygen and body temperature are all monitored continuously, with recovery insights served up after a workout.
The rest of the feature list reads like a proper fitness wearable. You get step counting, calorie tracking and menstrual cycle tracking, plus vibration alerts to nudge you when something needs your attention. Connectivity runs over Bluetooth, tying the ring to a companion app, and Casio quotes up to six days of battery life between charges — respectable for a device this small.
And it really is small. The CRW-H001M-8 weighs just 19 grams and measures 25.3 × 19.5 × 6 mm, so it should sit unobtrusively on your finger through the day and, more importantly, through the night when sleep tracking matters most. That compact footprint is the whole point: a ring you’ll actually keep wearing collects far more useful data than a watch you take off at bedtime.
The jump from novelty ring watch to health ring is a smart move for Casio. The smart-ring category has been heating up, and the company already had the industrial design chops to make something tiny and wearable feel special. Bolting continuous biometric monitoring onto that foundation is a logical next step — and one that gives the ring a reason to exist beyond the wow factor.
There is one significant catch. The CRW-H001M-8 went on sale on July 31, 2026, but only in China, priced at 1,990 yuan (~$294 USD). Casio has not announced a global launch, so buyers elsewhere are left watching from the sidelines for now.
If and when it does travel, the CRW-H001M-8 could be a compelling option for anyone who wants serious health tracking without strapping yet another screen to their wrist. Until then, it remains a tantalizing glimpse of where Casio’s most charming gadget is headed.
