Oura Ring 4 sizes are slightly different from standard ring sizes, so it is important to size yourself using our tools and to follow our sizing instructions. The Oura Ring 4 Sizing Kit allows for you, and those around you, to find the ideal fit before purchasing. You can also size yourself in stores where there is an Oura Ring 4 display. A properly fitting Oura Ring will result in the highest possible data accuracy, comfort, and overall experience.

• Free $10 gift card with purchase: Size yourself with the Oura Ring 4 Sizing Kit and receive a $10 Best Buy gift card to use towards the future purchase of an Oura Ring 4.
• Choose a finger: Oura Ring 4 works on all fingers and can be worn on either hand. Make sure to size the finger you plan to wear your Oura Ring on - your fingers can be different sizes. For optimal performance and accuracy, we recommend wearing your Oura Ring on your index, middle, or ring finger.
• Find your fit: Oura Ring 4 should fit snug around the base of your finger, but not to the point where it’s uncomfortable. The right size doesn’t feel too tight during daily wear or extended periods. When sizing yourself, the ring must fit over the largest part of your finger, like your knuckle.
• Wear test: Your fingers expand and contract based on environmental factors, so we recommend wearing your ring sizer for 24 hours to confirm your best fit. Your ring should not rotate as you go about normal daily tasks. If you size in store, make sure to spend time sizing and try multiple sizes.
• Sizes: Oura Ring 4 is available in sizes 4–15, and we currently do not offer half-sizes. Oura Ring sizes are slightly different from standard ring sizes, so you should not assume your ring size.
• Materials: Our sizing rings are made of plastic, while the Oura Ring 4 is crafted in full titanium for comfort. Due to the plastic mold used to make our ring sizers, they may seem less comfortable than the actual Oura Ring you’ll end up receiving.
• Free $10 gift card with purchase: Size yourself with the Oura Ring 4 Sizing Kit and receive a $10 Best Buy gift card to use towards the future purchase of an Oura Ring 4.
• Choose a finger: Oura Ring 4 works on all fingers and can be worn on either hand. Make sure to size the finger you plan to wear your Oura Ring on - your fingers can be different sizes. For optimal performance and accuracy, we recommend wearing your Oura Ring on your index, middle, or ring finger.
• Find your fit: Oura Ring 4 should fit snug around the base of your finger, but not to the point where it’s uncomfortable. The right size doesn’t feel too tight during daily wear or extended periods. When sizing yourself, the ring must fit over the largest part of your finger, like your knuckle.
• Wear test: Your fingers expand and contract based on environmental factors, so we recommend wearing your ring sizer for 24 hours to confirm your best fit. Your ring should not rotate as you go about normal daily tasks. If you size in store, make sure to spend time sizing and try multiple sizes.
• Sizes: Oura Ring 4 is available in sizes 4–15, and we currently do not offer half-sizes. Oura Ring sizes are slightly different from standard ring sizes, so you should not assume your ring size.
• Materials: Our sizing rings are made of plastic, while the Oura Ring 4 is crafted in full titanium for comfort. Due to the plastic mold used to make our ring sizers, they may seem less comfortable than the actual Oura Ring you’ll end up receiving.