
PRECISION SIZING
Get Your Perfect Fit Before You Commit
Oura's unique sizing ensures flawless comfort and accurate tracking every night.
Unique Sizing System
Purchase Credit Included
iOS & Android
All Finishes Available

WHY SIZE MATTERS
Smart Rings Demand Smarter Sizing Than Standard Jewelry
🎯 Non-Standard Precision Measurements
Oura Ring uses proprietary sizing to optimize sensor placement and biometric accuracy across your finger.
🔄 Full Credit Toward Ring
Your sizing kit purchase converts to credit when you order your Oura Ring 4.
Engineered for Accuracy, Designed for All-Day Comfort
Optimized Sensor Contact
Precise fit ensures continuous, accurate sleep and health data collection.
All-Day Wearability
Find the size that disappears on your finger during work, sleep, and workouts.
Every Finish Covered
Size confidently for Ceramic, Metallic, Black, Brushed Silver, Cloud, Gold, or Midnight.
iOS & Android Ready
Seamless compatibility with your smartphone ecosystem from day one.

PERFECT FOR
Anyone Ready to Optimize Their Health Tracking
- First-time smart ring users
- Gifting an Oura Ring
- Between standard ring sizes
- Upgrading from another wearable

THE DETAILS
Size Once, Wear Confidently for Years
Standard ring sizes don't account for the precision required by advanced biometric sensors. Oura's proprietary sizing system ensures your ring sits exactly where it needs to for accurate heart rate, temperature, and movement tracking throughout the night and day.
Try on multiple sizes in the privacy of your home, wear them during sleep and activity, and discover whichfit delivers both comfort and data accuracy. Your investment in sizing converts to credit toward your chosen finish—whether that's sleek Black, elegant Gold, or any other available option.
How It Works
Order Your Sizing Kit
Receive the complete range of Oura Ring sizes to test at home.
Test During Real Life
Wear different sizes during sleep, workouts, and daily activities to find your perfect match.
Order With Confidence
Apply your sizing kit credit toward your Oura Ring 4 in your chosen finish.
Frequently Asked Questions
Why can't I just use my standard ring size?
Oura Ring uses a proprietary sizing system optimized for sensor placement and all-day comfort. Standard jewelry sizes don't account for the precision required by biometric tracking technology, so trying the actual sizing kit ensures perfect fit and accuracy.
How does the purchase credit work?
When you purchase this sizing kit, you receive a credit equal to the purchase price to apply toward your Oura Ring 4 order. This makes sizing essentially risk-free.
Which finger should I wear my Oura Ring on?
The sizing kit lets you test different fingers to find optimal comfort and sensor accuracy. Most users prefer the index or middle finger for balanced comfort and data quality.
Is this compatible with both iOS and Android?
Yes, the Oura Ring 4 works seamlessly with both iOS and Android devices through the Oura App. The sizing kit helps you find the right fit regardless of your smartphone choice.
Can I use this to size for a gift?
Absolutely. The Gifting Sizing Kit option is perfect for ensuring your recipient gets the right fit before you commit to a specific finish and size.
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