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OURA

OURA Ring 4 Sizing Kit - Size Before You Buy

Based on 4,055 reviews
Condition: New
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$8.49
Save $1.51 was $10.00

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Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, Oct 31
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At a glance

Condition
New
Style
Sizing Kit
Model
JZ98-54870
GPS
No GPS
Shape
Round
Display Type
No Display
Band Material Type
Stainless Steel
Warranty
1 Year Manufacturer
Works with
Smartphone

Features 6

  • SIZE BEFORE YOU BUY - Oura Ring 4 sizes are different from standard ring sizes. Size yourself with the Oura Ring 4 Sizing Kit. For additional details, see From the brand section below
  • NOT STANDARD SIZING - Oura Ring 4 sizes are slightly different from standard ring sizes, so it is important to size yourself using our Oura Ring 4 Sizing Kit. Oura Ring 4 is available in sizes 4-15. There are no half sizes
  • COMFORT AND ACCURACY - A properly fitting Oura Ring will result in the highest data accuracy, comfort, and overall experience
  • CHOOSE A FINGER - Oura Ring 4 works on all fingers and can be worn on either hand. For optimal accuracy, we recommend wearing your Oura Ring 4 on your index, middle, or ring finger. Size the exact finger you plan to wear your Oura Ring 4 on

Description

The Oura Ring 4 Sizing Kit allows for you and those around you to find the ideal fit before purchasing. With a sizing kit purchase, a 10 credit will automatically be applied to your Oura Ring 4 at checkout. A properly fitting Oura Ring 4 will result in the highest possible data accuracy, comfort, and overall experience. 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. Oura Ring 4 works on all fingers and can be worn on either hand. For optimal accuracy, we recommend wearing your Oura Ring 4 on your index, middle, or ring finger.

Specs 23

Special Feature Heart Rate Monitor, Activity Tracker, Sleep Monitor
GPS No GPS
Shape Round
Brand OURA
Style Sizing Kit
Color Sizing Kit
Display Type No Display
Band Material Type Stainless Steel

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Oct 31

This item is non-returnable:

Final sale - No returns

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • Zip Pay in 4
  • Financing through Apple Pay
  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

Buy the kit. It will give you sizing peace of mind!
Style: Sizing Kit Color: Sizing Kit Size: Sizing Kit
This little sizing kit works great. Was able to get the correct size. I decided to wear the size I wanted from the kit for a few days to make sure it fit well when my hands changed throughout the day. When I finally purchased my Oura ring I had the perfect size. No issues at all.
Reviewed in the United States on July 16, 2026 by Mikayla
Ring sizing comes in handy!
Style: Sizing Kit Color: Gifting Sizing kit Size: Gifting Sizing Kit
Had to buy this so I could get exact size for the Aura ring. But love it for sizing! Worth it
Reviewed in the United States on September 1, 2026 by Dsh
You HAVE TO BUY OURA SIZING KIT
Style: Sizing Kit Color: Sizing Kit Size: Sizing Kit
Review Image by Amazon Customer
So happy I bought the sizing kit YOU NEED IT. Oura does not come in standard sizing. I typically wear a 7.5 US women’s ring size and the Oura size 9 was a perfect fit for my index size 8 was a bit loose on my ring finger. Shocking. So glad i didn’t purchase a 7 or an 8 or it would’ve been way to tight or loose. Your fingers swell in the morning so keep this in mind. ... show more
Reviewed in the United States on June 29, 2026 by Amazon Customer
Glad I got the sizing kit first
Style: Sizing Kit Color: Gifting Sizing kit Size: Gifting Sizing Kit
Review Image by Ashley
I’m glad I bought this sizing kit before purchasing my Oura ring because I would have purchased the wrong size. This is great because not only does it help ensure you get the correct size but it also helped me with knowing how it would fit on my finger before buying it. Looking at pictures it looks a little bulky so the sizing kit gives me an idea of what it would feel like wearing it. The sizing kit came with 12 different sizes so you will be able to try multiple sizes. ... show more
Reviewed in the United States on June 28, 2026 by Ashley
NO REFUND OPTION
Style: Sizing Kit Color: Gifting Sizing kit Size: Gifting Sizing Kit
NO REFUND OPTION: I bought this sizing kit because I thought I was going to purchase an Oura Ring. However, after it arrived, my sister-in-law was visiting and told me she had bought an Oura Ring and did not like it or find it useful. She felt it was a waste of money for her, so I decided not to go forward with buying the ring. I never even opened the package, but then I found out the sizing kit could not be returned. That means the money was basically just thrown away. It was not clear to me when I purchased it that all sales were final. If you are not 100% sure you are going to buy the Oura Ring, I would not recommend buying this sizing kit. ... show more
Reviewed in the United States on July 1, 2026 by LaurieH
Worked Great To Find My Oura Ring Size! Discount Was Automatically Applied To The Ring.
Style: Sizing Kit Color: Sizing Kit Size: Sizing Kit
Review Image by Christine
Review Image by Christine
I was hesitant to buy this because I worried it would be complicated to apply the discount from buying the sizing kit to the ring, but it was completely automatic (I bought both through Amazon so I can't say it is the same anywhere else, but on Amazon it was automatically applied to my checkout)! I didn't have to do anything. The sizing kit works great! It came in a box with several different sizes from very small to very large (size 4 - size 15). The size you are wearing is on each band so you won't forget which size you are wearing. The size number raises up, as part of the same material of the ring, meaning it cannot fade off, and you will always know which size each ring is. I found the most comfortable fit and wore it for a few days to make sure it was snug but not uncomfortable. The ideal fingers for the Oura ring are the pointer, middle, or ring finger. If you are prone to swelling you could size it to your ring or pointer and if you have swelling, move it to your middle finger. It is good to buy the kit to be sure, but I will say that the size I bought is also my ring size. I am still happy I bought the sizing kit and didn't risk having to do a return if it were different (and it can be), and it didn't cost me anything once I bought the ring. If you know you want the Oura ring, don't hesitate to buy the kit, as you will get your money back when you buy the ring, and it will save you the hassle of a return. My daughter ended up taking the smaller rings and decorating them, so we got some use out of the extra rings, as well! ... show more
Reviewed in the United States on March 5, 2025 by Christine
A Must-Have Before Ordering Your Oura Ring
Style: Sizing Kit Color: Sizing Kit Size: Sizing Kit
This sizing kit made choosing the right Oura Ring size easy and stress-free. The sample rings are comfortable to wear and helped me find the perfect fit before placing my order. I highly recommend wearing the test size for at least a full day and overnight since finger size can change throughout the day. It saved me from ordering the wrong size and made the whole process much easier. Definitely worth it if you’re planning to buy an Oura Ring. ... show more
Reviewed in the United States on June 9, 2026 by Antonia
Works
Style: Sizing Kit Color: Sizing Kit Size: Sizing Kit
I got the Oura Ring 4 sizing kit to figure out my correct size before ordering the actual ring, and it definitely served its purpose. The different sample sizes made it easy to test what felt most comfortable throughout the day and even overnight. That said, once I found my size, I wasn’t really sure what to do with the kit afterward—it just kind of sits there. It would be nice if there was some kind of return or reuse option. Overall, it’s helpful and pretty much necessary for getting the right fit, but not something you’ll have much use for after that. ... show more
Reviewed in the United States on April 1, 2026 by Mystic Mama Moonlight Market
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