Oura has launched the Ring 5, a smart ring that is 40% smaller than its predecessor and, at 6.09mm wide and 2.29mm thick, is the smallest smart ring on the market. The ring weighs as little as 2 grams depending on size, down from the Ring 4’s 7.99mm width and 2.88mm thickness. Despite the shrinkage, Oura says the Ring 5 retains the same sensor accuracy and offers up to nine days of battery life.

“We have finally achieved what I think seems like a real technological miracle,” CEO Tom Hale told CNBC. “This is what our members have been asking us for, for years.” The Ring 5 is available for preorder immediately at $399 for black and silver finishes, or $499 for gold, stealth, brushed silver, and deep rose. Shipping begins 4 June. An Oura membership is required at $5.99 per month or $69.99 per year.

Blood pressure signals and AI health monitoring

The Ring 5 introduces a feature Oura calls Health Radar, an AI-powered monitoring system that continuously tracks biometric signals including body temperature, respiratory rate, and heart rate variability in the background. When Health Radar detects patterns that suggest strain, it surfaces alerts to the wearer. Oura has built its reputation on passive health tracking that works without screens or notifications, and Health Radar extends that approach with predictive capabilities.

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The most notable new feature is Blood Pressure Signals, which detects shifts and patterns that may indicate cardiovascular strain. The ring does not measure blood pressure directly, an important distinction. Instead, it tracks biometric patterns that correlate with rising blood pressure and alerts users when it detects concerning trends. The feature positions Oura in a growing market for continuous cardiovascular monitoring, alongside companies developing cuffless blood pressure measurement for wrist-worn devices.

A Nighttime Breathing feature provides a 30-day rolling view of sleep-related breathing patterns and disturbances, giving users data that could prompt conversations with a doctor about conditions like sleep apnoea. 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, providing a longitudinal view of their medication journey.

A company heading for the public markets

The Ring 5 launch comes at a pivotal moment for Oura as a business. The company confidentially filed for a US IPO and is valued at approximately $11 billion following a $900 million Series E round led by Fidelity in late 2025. Total capital raised stands at roughly $1.5 billion, with additional backing from ICONIQ, Whale Rock, and Atreides. Oura also secured a $250 million revolving credit facility arranged by JPMorgan, Goldman Sachs, Bank of America, Barclays, Citi, and Wells Fargo.

The financial trajectory is aggressive. Oura reported revenue above $500 million in 2024, roughly doubled that to approximately $1 billion in 2025, and Hale has said the company could reach close to $2 billion in 2026 sales. The Ring 5 is designed to accelerate that growth by addressing the single most common complaint from existing members: the ring was too thick.

The smart ring market is getting crowded

Oura created the smart ring category but no longer has it to itself. Samsung launched the Galaxy Ring at $399, matching Oura’s entry price, and integrating it with the Samsung Health ecosystem. The Galaxy Ring weighs as little as 2.3 grams and has proven popular with users who find smartwatches too bulky for sleep tracking. Apple has not launched a ring but has been reported to be exploring the form factor, and CCS Insight has predicted an Apple Ring could arrive as early as 2026.

Wearable fitness trackers have evolved from step counters to medical-grade monitoring devices, and the smart ring sits at the intersection of convenience and clinical ambition. The category appeals to users who want continuous health data without wearing a screen on their wrist, and the Ring 5’s smaller size is designed to make the trade-off even easier.

For Oura, the Ring 5 is both a product launch and a pre-IPO statement. A smaller, more capable ring arriving alongside an IPO filing signals that the company believes it can sustain its growth rate as a public company. The health wearable market is increasingly competitive, but Oura’s bet is that the ring form factor, combined with AI-driven health insights, gives it a category advantage that watches and bands cannot match.