Oura Smart Ring 4 Size 9 - Stealth (JZ90-54218-09)

Oura Ring 4 – Smarter Insights, Better Health

Meet the Oura Ring 4, the latest evolution of the revolutionary smart ring designed to bring you closer to what matters most—your health. Featuring an updated all‑titanium design and powered by Smart Sensing, Oura Ring 4 doesn’t just measure your biometrics; it adapts to you. Receive accurate insights into more than 30 biometrics, including sleep, readiness, activity, heart health, stress, and women’s health. With a comfortable, screen‑free design and up to 8 days of battery life, Oura Ring is built for 24/7 wear so you can forget it’s even on.

Key Features

Smart Sensing Accuracy

Oura Ring 4’s advanced Smart Sensing platform adapts to your unique finger and lifestyle, delivering precise, continuous biometric data day and night.

Designed for All‑Day Comfort

The first all‑titanium smart ring, Oura Ring 4 offers enhanced durability with a gentle feel, even for sensitive skin. It’s water-resistant up to 100m, made for everyday wear, and crafted with a seamless titanium interior.

Long-Lasting Battery

Enjoy up to 8 days of battery life with no screens and no vibrations, helping you stay focused on the present.

Health & Wellness Tracking

Sleep

Wake up to in‑depth sleep analysis covering sleep staging, blood oxygen levels, HRV, and nighttime heart rate—designed to help you improve your rest and overall well‑being.

Activity

Track daily activity, steps, calories burned, and workouts. Oura helps you find the right balance between movement and recovery, whether you're running errands or running a marathon.

Readiness

The Oura Readiness Score uses over 30 body signals—including temperature, heart rate, HRV, and sleep—to help you understand how prepared your body is for the day ahead.

Stress

Identify signs of stress and see how well your body is coping. Oura guides you in incorporating self‑care and understanding responses to long‑term stressors.

Illness Detection

Oura monitors shifts in temperature and heart rate to help you detect early signs that you may be getting sick.

Women’s Health

Understand your cycle and how it affects your mood, sleep, and activity. Oura tracks changes throughout your cycle and can predict your period up to 30 days in advance.

Heart Health

Monitor daily heart rate and HRV while gaining insights into your Cardiovascular Age and Cardio Capacity—key indicators of overall health.

Product Specifications

Included Accessories:
Oura Ring, Charging Dock & USB Cable

Battery:

• Capacity: 14.5mAh
• Battery Life: Up to 8 days
• Charging Time: 80 minutes

Sensors & Tracking:

• Red & infrared LEDs for blood oxygen measurement
• Green & infrared LEDs for 24/7 heart rate & HRV
• Digital temperature sensor
• Accelerometer for all‑day activity tracking

Materials & Durability:

• Non‑allergenic titanium (inner & outer surfaces)
• Seamless titanium interior
• Water‑resistant up to 100m/328ft
• Minor scratches from regular wear are normal

Connectivity:

• Bluetooth Low Energy
• Automatic firmware updates via the Oura App
• EMF‑safe
• Supports airplane mode
• FCC‑certified

Compatibility:

• Oura App available in English, Finnish, Japanese, German, French, Spanish, Italian, Norwegian, Swedish, Czech, Dutch, and Danish
• Supports metric & imperial units
• Integrates with 40+ apps
• Works on iOS and Android

Dimensions & Weight:

• Width: 7.90mm
• Thickness: 2.88mm (similar to a wedding band)
• Weight: 3.3–5.2g depending on size