A properly fitting Oura Ring will ensure the highest possible data accuracy, comfort, and overall experience. Below are some tips to help you determine your ideal Oura Ring size.
The sizing for Oura Ring 4 is slightly different from Oura Ring Gen3. If you're switching between these different ring generations or uncertain about your size, make sure to use the right Oura Ring Sizing Kit for an accurate fit. The Oura Ring 4 Sizing Kit includes white ring sizers, and the Oura Ring Gen3 Sizing Kit includes black ring sizers.
How to Choose Your Size
How to Remove & Care for Your Ring
Between Sizes?
How to check your ring size
We don't offer the option to buy individual sizing kits from the Oura online store. If you choose the Size Later option, a sizing kit is included as part of your Oura Ring purchase.
However, many authorized retailers sell sizing kits separately. When you purchase one, you'll receive a credit towards a future Oura Ring purchase from that retailer.
Once you're finished with the sizing kit, you don't need to return it. Instead, feel free to pass it along to a friend or family member who might be interested in Oura. Otherwise, please recycle your sizing kit.
If you received a sizing kit from a friend or family member or have already determined your Oura Ring size, you can select your size directly while purchasing.
How to Choose Your Size
Our ring sizers are meant to serve as guidelines for selecting your size and are not reflective of the quality and feel of the Oura Ring you'll receive after updating your order.
1. Open Your Sizing Kit
Inside your sizing kit, you’ll find plastic ring sizers (sizes 4–15 for Oura Ring 4, sizes 6-13 for Gen3). Oura Ring sizes are slightly different than standard US ring sizes. We don't offer half sizes.
Oura Ring and ring sizers are the same width and circumference. However, the Oura Ring itself weighs slightly more due to material differences.
2. Choose Your Finger
The Oura Ring works on all fingers and can be worn on either hand.
For optimal performance and accuracy, we recommend wearing your Oura Ring on your index finger.
If you prefer another finger, the middle or ring fingers are the next best but try to avoid fingers with large knuckles (where the base of your finger is narrower than the knuckle). Try a few sizes on different fingers to find the ideal fit.
You can move your ring between fingers and hands if you'd like or ever need to due to changes in finger size.
3. Confirm Ring Orientation
Oura Ring 4 Wear the ring sizer with the size number visible on the top of the hand.
Oura Ring Gen3: The sensor bumps inside the ring sizer should be on the pad (palm side) of your finger.
4. Ensure a Comfortable Fit
Your Oura Ring should fit tightly and securely around the base of your finger. The right size is one that's comfortable to wear for extended periods and doesn't feel too tight during daily wear. The ring size you select shouldn't slide off easily but should come off with a bit of soap and water.
5. Test the Snugness
Test the fit by making a fist while wearing your ring sizer. If you see a gap between the top of your finger and the inside of the ring, you might need a smaller size.
6. Wear for 24 Hours
Your fingers expand and contract based on environmental factors, so we recommend wearing your ring sizer for at least 24 hours, including while sleeping, to ensure the best fit. Your ring should not rotate during everyday activities.
7. Confirm Your Ring Size
Once you've landed on your ideal size:
- If you bought your sizing kit from the Oura online store, sign in to My Account and confirm your Oura Ring size. You can also find direct links to My Account in your sizing kit order and shipping confirmation emails. Once your confirmed ring size has been shipped, you'll receive a tracking email from us, and you can also find the tracking number in My Account
- If you bought your sizing kit from an authorized retailer, return to the retailer and purchase your ring size
How to Remove & Care for Your Ring
To gently remove your ring, wash your hands with soap and water and slide the ring off your finger.
Whenever you wash your hands with your Oura Ring on, you can follow these best practices to prevent irritation:
- Once you're done washing your hands, slide your Oura Ring up your finger and dry the base of your finger
- Next, slide your Oura Ring back down to the base of your finger and dry the area above your ring. This will help prevent water from becoming trapped underneath your ring
Stuck Between Sizes?
We recommend choosing the smaller of the two for the following reasons:
Accuracy
The sensors on the inside of your Oura Ring should always remain in contact with the pad of your finger. A more snug fit is known to create a stronger signal between the LED sensors inside your Oura Ring and the arteries beneath your skin by eliminating space/gaps.
Materials
Because our ring sizers are made of plastic, they may feel "stickier" on your skin and may not slide off as easily as the actual Oura Ring.
How to Check Your Ring Size
If you already have a ring, you can find your ring size either inside the ring itself or in the Oura App. The size is marked on the inner side of the ring, opposite the sensors. To check in the Oura App, tap the icon in the upper-right corner of the home screen, then swipe left to view your ring's model and size.
