Oura Ring 4 Sizing Kit - Size Before You Buy The Oura Ring 4 - Unique Sizing, Not Standard US Ring Sizes - Receive Credit for Purchase
Condition: New
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- – 4-month term
- – No impact on credit to apply
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Payment plans are offered through our trusted finance partners Klarna, Affirm, Afterpay, Apple Pay, and PayTomorrow. No-credit-needed leasing options through Acima may also be available at checkout.
Learn more about financing & leasing here.
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Availability:
In Stock.
Arrives
Monday, Mar 23
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Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
Features
- 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
- HOW IT SHOULD FIT - Oura Ring 4 should fit securely and comfortably at the base of your finger. Your ring should not rotate as you go about normal daily tasks. We recommend wearing your ring sizer for at least 24 hours to confirm your best fit
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.
Package Dimensions: 6.57 x 4.45 x 0.47 inches
Item Weight: 1.76 ounces
Item model number: JZ98-54870
Date First Available: October 3, 2024
Manufacturer: Oura
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Monday, Mar 23
- Klarna Financing
- Affirm Pay in 4
- Affirm Financing
- Afterpay Financing
- PayTomorrow Financing
- Financing through Apple Pay
Learn more about financing & leasing here.
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Top Amazon Reviews
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
This was absolutely perfect to help me determine my ring size before buying the oura ring. The fit of the tester band was the exact same size as the oura ring. I loved that I was able to wear it for a day and try it out before buying the actual ring. I found this kit very helpful in finding the most comfortable size
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Reviewed in the United States on February 13, 2026 by Sydney Walsh
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
It does exactly what it says it does. The rings are comfortable to wear and made it easy to figure out the right size before ordering the actual Oura Ring. I also appreciated being able to wear it for a full day to see how it felt during normal activities and while sleeping. Simple, accurate, and definitely worth using to avoid sizing issues
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Reviewed in the United States on February 3, 2026 by Diana
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
This sizing kit is hands down the best thing to purchase before ordering an Oura Ring. The sizing runs differently than regular jewelry, so trying the sample rings first made a huge difference in choosing the perfect fit. I loved being able to wear a size for a full day to see how it felt during normal activities, sleeping, and slight finger swelling. It gave me confidence that I was ordering the correct size and avoided the hassle of returns or exchanges. If you’re even slightly unsure about sizing, get this first. It’s a small step that saves time, stress, and money in the long run. Highly recommend! ⭐⭐⭐⭐⭐
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Reviewed in the United States on February 14, 2026 by Natalie
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
Within the 6 months of having this ring I’ve noticed that scratches have only really appeared where I hit my finger against my computer mouse at work. The rest of the ring looks great! I have some sleep and health issues so this tracking has immensely helped me find out what I need to adjust. Based on your sleep score, temperature, and heart rate, the app will let you know if something is going on - especially illnesses. It’ll let you know something minor is straining your body when you are going to be sick the following day, then show major signs when you’re actually sick, which gives great peace of mind. I also started a new medication and my general scores lately, along with other factors, have shown that I need to revisit this medication choice. I’ve also really enjoyed the cycle tracking while being off of birth control, this along with ovulation testing has been the best hormone free birth control. This has been the most accurate tracking and prediction I’ve had, in comparison to Flo and Stardust. These rings are amazing if you’re looking to have some motivation for activity, cycle tracking, sleep monitoring, and general peace of mind.
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Reviewed in the United States on February 16, 2026 by Averi Averi
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
The media could not be loaded. The Oura Ring 4 sizing kit was really helpful in finding my perfect fit before ordering the actual ring. The different sample sizes made it easy to test comfort for a few days. I liked that it’s lightweight and gives a good idea of how the real ring will feel. The only downside is that the samples are plain and not the real material, so it’s hard to tell exactly how it’ll look—but overall, super useful and worth trying before buying!
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Reviewed in the United States on October 20, 2025 by Nikita wakchaure
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
If you’re planning to buy the Oura Ring 4, this sizing kit is almost essential. Here’s my straight-talk review: What I liked: The sizing kit gives you multiple trial rings (sizes 4-15) to test your finger and fit. Best Buy +2 Android Authority +2 It helps you understand that Oura’s ring sizing doesn't match standard ring sizes — many users found they needed a different size than their usual jewelry ring. The fit matters a lot: the company says a proper fit leads to better comfort and data accuracy. You typically receive a credit toward your actual ring purchase, so the sizing kit effectively reduces risk. One small caveat: The sizing rings are made of plastic and feel different than the actual titanium ring. Some people notice differences in how the plastic kit fits versus the final product. You’ll need to wear the sizing ring for at least 24 hours (and ideally through normal daily activities) to check comfort, swelling, finger variation. Bottom line: If you’re buying the Oura Ring 4, get the sizing kit first. It takes away a lot of guesswork and prevents the hassle of ordering a ring that’s too loose or too tight. Measure your finger, test it over a day or two, pick the best fit — then buy the actual ring. This way your investment pays off and you get the full benefit of the ring.
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Reviewed in the United States on October 21, 2025 by L. Bell
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
Super helpful in figuring out the correct ring size for me. Way different than I had assumed it would be. If I had ordered the actual ring fist without the sizing set I’d have been returning! Was great to wear the sizing kit for a while thru daily activities before dropping a few hundred bucks on the real thing.
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Reviewed in the United States on March 5, 2026 by Carolyn
Style: Sizing Kit
Color: Sizing Kit
Size: Sizing Kit
Purchased the oura ring after sizing it with this tool. Works perfectly. I am thankful to Amex for their Oura ring promotion, and I am super happy to have invested in the equipment.
Reviewed in the United States on January 11, 2026 by Brad Slavin