Device
Oura Ring 3 vs 4: Which Should You Buy?
Oura Ring 3 vs 4: Which Should You Buy?
The Oura Ring 4 launched in October 2024 with a redesigned sensor platform, wider sizing range, and a sleeker profile. If you are currently wearing a Gen 3 and wondering whether to upgrade, or you are shopping for your first smart ring and want to know whether a used Gen 3 is worth considering, this comparison breaks down what actually changed and what it means for the metrics you care about.
The short answer: the Ring 4 is a meaningful hardware upgrade over Gen 3, not just a cosmetic refresh. The Smart Sensing platform with 18-path PPG represents a genuine step up in signal quality, which flows through to more accurate sleep staging, HRV, and respiratory rate tracking. Whether that improvement justifies the price difference depends on what you are tracking and what you already have.
Gen 3 is no longer sold through Oura's official store. If you are looking at it, you are looking at a refurbished unit or a secondhand purchase. Ring 4 starts at $349 plus the $5.99/month or $69.99/year membership that covers both generations.
Key Takeaways
Ring 4's Smart Sensing platform provides meaningfully better accuracy for sleep staging, HRV, and respiratory rate compared to Gen 3's sensor array.
Ring 4 adds sizes 4-5 and 14-15 that Gen 3 never offered, making it accessible to people who could not wear the older ring.
Gen 3 still works with the current Oura app and receives software updates, but its days of hardware support will eventually end.
Quick Verdict
Buy Ring 4 if: you are buying new, your finger is size 4-5 or 14-15, or you want the most accurate biometric tracking available from Oura.
Consider Gen 3 if: you find a well-priced refurbished unit and your primary interest is sleep and heart rate basics rather than cutting-edge accuracy.
Skip Gen 3 entirely if: you plan to wear it for more than 2-3 years. Hardware support cycles end, and Ring 4's sensor gap will widen over time.
Oura Ring Gen 3 Overview
The Gen 3 launched in November 2021 and was Oura's first ring to track blood oxygen (SpO2), period prediction, daytime heart rate, and skin temperature trend. It represented a significant leap over the Gen 2 and established Oura as the serious wearable choice for sleep tracking enthusiasts and researchers.
Its sensor array includes green, red, and infrared LEDs alongside an accelerometer and a digital temperature sensor. Battery life runs 4-7 days depending on usage, and it is available in sizes 6-13. The Gen 3 tracks sleep latency, sleep stages, HRV, resting heart rate, respiratory rate during sleep, and SpO2.
It remains a capable ring. Gen 3 users still receive app updates, and the current Oura app works fully with both generations. The limitation is hardware. The PPG signal path in Gen 3 is narrower than Ring 4's, which means less raw data going into the sleep staging and HRV algorithms. The gap is most visible in people with challenging skin tones or fingers that do not sit flat against the ring surface.
Gen 3 specs at a glance:
Battery: 4-7 days
Sizes: 6-13
Sensors: Green, red, IR LEDs; accelerometer; temperature sensor
Materials: Titanium shell with inner coating
Water resistance: 100m
Price: Discontinued from Oura store; refurbished/secondhand only
Oura Ring 4 Overview
Ring 4 introduced Smart Sensing, an 18-path multi-wavelength PPG system that samples more signal paths than Gen 3's single-path approach. In practice, this means the ring can better account for variations in how light interacts with different skin tones and ring positions, producing more consistent accuracy across a broader population.
The design is fully titanium inside and out, with recessed sensors that reduce the friction point felt during the day. It is available in six finishes and covers sizes 4-15, the widest range of any smart ring. Battery life extends to up to 8 days. The Oura app was redesigned alongside Ring 4, reorganizing data into three tabs: Today, Vitals, and My Health. Sleep apnea detection was also added as a feature tracked over time using overnight respiratory and oxygen data.
Ring 4 specs at a glance:
Battery: Up to 8 days
Sizes: 4-15
Sensors: 18-path multi-wavelength PPG (Smart Sensing); accelerometer; temperature sensor
Materials: Full titanium (inside and out)
Water resistance: 100m
Data storage: Up to 2 weeks on-ring
Price: Starting at $349 + $5.99/month or $69.99/year membership
Head-to-Head: What Actually Changed
Sensor accuracy
This is the biggest practical difference. Ring 4's 18-path PPG means it collects more raw signal to derive sleep stages, HRV, and heart rate overnight. Gen 3 uses a narrower sensor path that performs well for most users but shows larger variance in people with certain skin tones and ring-fit issues. If you have struggled with Gen 3 accuracy, Ring 4 is likely to perform better on your wrist.
Battery life
Ring 4 gets up to 8 days versus Gen 3's 4-7 day range. In practice, both rings need charging roughly once a week. The extra day in Ring 4 is a genuine buffer but not a fundamental change in how you manage the device.
Sizing range
Ring 4's sizes 4-15 versus Gen 3's 6-13 matters a lot if you have particularly small or large fingers. Many people who tried Gen 3 and found it too large to wear comfortably now have options with Ring 4.
Design and comfort
The recessed sensors and full titanium interior make Ring 4 notably smoother against the skin. Gen 3 has a slight ridge where the sensors protrude. For daily wear during exercise and sleep, this is a noticeable comfort difference that accrues over months of use.
New features
Ring 4 added Cycle Insights with Fertile Window tracking, a redesigned Daytime Stress view that links stress spikes to activities, and the updated app interface. These are software features, and some have been backported to Gen 3 through app updates. Sleep apnea pattern detection is available on both generations through the app.
Blood oxygen tracking
Both rings track SpO2, and overnight blood oxygen data is available in both. Ring 4's improved PPG path provides a more stable optical signal for this measurement, though both rings meet the accuracy bar needed for wellness tracking.
Who Should Upgrade From Gen 3 to Ring 4?
Upgrade if accuracy has been an issue. If your Gen 3 occasionally produces sleep stages that do not match how you felt you slept, or your HRV and respiratory rate data has seemed inconsistent, Ring 4's broader sensor path is likely to improve results for you specifically.
Upgrade if sizing is the problem. Several Gen 3 owners found their ring too large after months of wear (fingers change size with temperature and weight) or needed a size that Gen 3 did not offer. Ring 4's wider range solves both.
Upgrade if you care about longevity. Gen 3 is discontinued hardware. Software support will eventually end, as it did for Gen 2. Ring 4 is the current platform and will receive hardware-matched feature development for several more years.
Who Should Stay on Gen 3 or Skip Ring 4?
If your Gen 3 is accurate and comfortable, the practical day-to-day difference from upgrading is modest for most users. Sleep scores, HRV trends, and temperature trend data are the metrics most people rely on, and Gen 3 handles these acceptably for the majority of users in sizes 6-13 with typical skin tones.
If cost is the primary concern, a well-priced Gen 3 refurbished unit is still a capable sleep tracking smart ring. The membership cost is identical, so your ongoing monthly cost is the same regardless of which hardware generation you wear.
One practical note: if you are buying a used Gen 3, check that it comes with the original sizing kit and confirm the ring size before buying. Ring sizing is the single biggest complaint among Oura users, and ordering the wrong size on a secondhand purchase leaves you with no recourse.
Whichever ring you use, the data it produces is only as useful as what you do with it. Pairing Oura's overnight metrics with a planning app that schedules your day around your energy levels closes the loop between tracking and action. Lifestack does exactly this: it reads your energy patterns and builds your schedule around them, so that a night of poor sleep or a low HRV reading actually changes how your tasks are timed rather than just being a number you note and forget.
FAQ
Is Oura Ring Gen 3 still sold?
No. Oura discontinued Gen 3 sales from their official store when Ring 4 launched in October 2024. Gen 3 units are available through refurbished sellers and secondhand marketplaces, but they come without Oura's retail warranty.
What is the main difference between Oura Ring 3 and 4?
The primary hardware difference is the sensor platform. Ring 4 uses an 18-path multi-wavelength PPG system (Smart Sensing) compared to Gen 3's narrower sensor array. This improves accuracy for sleep staging, HRV, and respiratory rate, particularly for users where Gen 3 produced inconsistent results. Ring 4 also extends the size range to 4-15 (from Gen 3's 6-13) and improves battery life to up to 8 days.
Can I use my Gen 3 with the new Oura app?
Yes. The current Oura app supports both Ring 4 and Gen 3. Many software features have been backported to Gen 3, including sleep apnea detection and the redesigned app interface. Hardware-dependent features that require Ring 4's sensors will not be available on Gen 3.
Is Ring 4 worth the upgrade from Gen 3?
For most users who are satisfied with their Gen 3 accuracy and comfort, the upgrade is optional rather than urgent. For users who have experienced accuracy issues, struggle with ring sizing, or want to stay on supported hardware long-term, Ring 4 is the right move. The $349 starting price (same membership) is the practical barrier for most people considering the switch.
Does Ring 4 track sleep apnea?
Ring 4 and Gen 3 both support Oura's sleep apnea detection feature through the app. The feature looks for consistent patterns in overnight respiratory rate and blood oxygen data rather than diagnosing individual events. It is a screening signal, not a medical diagnostic tool, and positive signals should be followed up with a clinical sleep study.
What size should I order for Oura Ring 4?
Oura ships a free sizing kit before your ring purchase. Use it over at least 2-3 days and check your finger size at different times of day. Fingers change size with temperature, hydration, and activity. Most people size up one size from what they measure in the morning, as fingers tend to be at their smallest after waking.
The Oura Ring 4 launched in October 2024 with a redesigned sensor platform, wider sizing range, and a sleeker profile. If you are currently wearing a Gen 3 and wondering whether to upgrade, or you are shopping for your first smart ring and want to know whether a used Gen 3 is worth considering, this comparison breaks down what actually changed and what it means for the metrics you care about.
The short answer: the Ring 4 is a meaningful hardware upgrade over Gen 3, not just a cosmetic refresh. The Smart Sensing platform with 18-path PPG represents a genuine step up in signal quality, which flows through to more accurate sleep staging, HRV, and respiratory rate tracking. Whether that improvement justifies the price difference depends on what you are tracking and what you already have.
Gen 3 is no longer sold through Oura's official store. If you are looking at it, you are looking at a refurbished unit or a secondhand purchase. Ring 4 starts at $349 plus the $5.99/month or $69.99/year membership that covers both generations.
Key Takeaways
Ring 4's Smart Sensing platform provides meaningfully better accuracy for sleep staging, HRV, and respiratory rate compared to Gen 3's sensor array.
Ring 4 adds sizes 4-5 and 14-15 that Gen 3 never offered, making it accessible to people who could not wear the older ring.
Gen 3 still works with the current Oura app and receives software updates, but its days of hardware support will eventually end.
Quick Verdict
Buy Ring 4 if: you are buying new, your finger is size 4-5 or 14-15, or you want the most accurate biometric tracking available from Oura.
Consider Gen 3 if: you find a well-priced refurbished unit and your primary interest is sleep and heart rate basics rather than cutting-edge accuracy.
Skip Gen 3 entirely if: you plan to wear it for more than 2-3 years. Hardware support cycles end, and Ring 4's sensor gap will widen over time.
Oura Ring Gen 3 Overview
The Gen 3 launched in November 2021 and was Oura's first ring to track blood oxygen (SpO2), period prediction, daytime heart rate, and skin temperature trend. It represented a significant leap over the Gen 2 and established Oura as the serious wearable choice for sleep tracking enthusiasts and researchers.
Its sensor array includes green, red, and infrared LEDs alongside an accelerometer and a digital temperature sensor. Battery life runs 4-7 days depending on usage, and it is available in sizes 6-13. The Gen 3 tracks sleep latency, sleep stages, HRV, resting heart rate, respiratory rate during sleep, and SpO2.
It remains a capable ring. Gen 3 users still receive app updates, and the current Oura app works fully with both generations. The limitation is hardware. The PPG signal path in Gen 3 is narrower than Ring 4's, which means less raw data going into the sleep staging and HRV algorithms. The gap is most visible in people with challenging skin tones or fingers that do not sit flat against the ring surface.
Gen 3 specs at a glance:
Battery: 4-7 days
Sizes: 6-13
Sensors: Green, red, IR LEDs; accelerometer; temperature sensor
Materials: Titanium shell with inner coating
Water resistance: 100m
Price: Discontinued from Oura store; refurbished/secondhand only
Oura Ring 4 Overview
Ring 4 introduced Smart Sensing, an 18-path multi-wavelength PPG system that samples more signal paths than Gen 3's single-path approach. In practice, this means the ring can better account for variations in how light interacts with different skin tones and ring positions, producing more consistent accuracy across a broader population.
The design is fully titanium inside and out, with recessed sensors that reduce the friction point felt during the day. It is available in six finishes and covers sizes 4-15, the widest range of any smart ring. Battery life extends to up to 8 days. The Oura app was redesigned alongside Ring 4, reorganizing data into three tabs: Today, Vitals, and My Health. Sleep apnea detection was also added as a feature tracked over time using overnight respiratory and oxygen data.
Ring 4 specs at a glance:
Battery: Up to 8 days
Sizes: 4-15
Sensors: 18-path multi-wavelength PPG (Smart Sensing); accelerometer; temperature sensor
Materials: Full titanium (inside and out)
Water resistance: 100m
Data storage: Up to 2 weeks on-ring
Price: Starting at $349 + $5.99/month or $69.99/year membership
Head-to-Head: What Actually Changed
Sensor accuracy
This is the biggest practical difference. Ring 4's 18-path PPG means it collects more raw signal to derive sleep stages, HRV, and heart rate overnight. Gen 3 uses a narrower sensor path that performs well for most users but shows larger variance in people with certain skin tones and ring-fit issues. If you have struggled with Gen 3 accuracy, Ring 4 is likely to perform better on your wrist.
Battery life
Ring 4 gets up to 8 days versus Gen 3's 4-7 day range. In practice, both rings need charging roughly once a week. The extra day in Ring 4 is a genuine buffer but not a fundamental change in how you manage the device.
Sizing range
Ring 4's sizes 4-15 versus Gen 3's 6-13 matters a lot if you have particularly small or large fingers. Many people who tried Gen 3 and found it too large to wear comfortably now have options with Ring 4.
Design and comfort
The recessed sensors and full titanium interior make Ring 4 notably smoother against the skin. Gen 3 has a slight ridge where the sensors protrude. For daily wear during exercise and sleep, this is a noticeable comfort difference that accrues over months of use.
New features
Ring 4 added Cycle Insights with Fertile Window tracking, a redesigned Daytime Stress view that links stress spikes to activities, and the updated app interface. These are software features, and some have been backported to Gen 3 through app updates. Sleep apnea pattern detection is available on both generations through the app.
Blood oxygen tracking
Both rings track SpO2, and overnight blood oxygen data is available in both. Ring 4's improved PPG path provides a more stable optical signal for this measurement, though both rings meet the accuracy bar needed for wellness tracking.
Who Should Upgrade From Gen 3 to Ring 4?
Upgrade if accuracy has been an issue. If your Gen 3 occasionally produces sleep stages that do not match how you felt you slept, or your HRV and respiratory rate data has seemed inconsistent, Ring 4's broader sensor path is likely to improve results for you specifically.
Upgrade if sizing is the problem. Several Gen 3 owners found their ring too large after months of wear (fingers change size with temperature and weight) or needed a size that Gen 3 did not offer. Ring 4's wider range solves both.
Upgrade if you care about longevity. Gen 3 is discontinued hardware. Software support will eventually end, as it did for Gen 2. Ring 4 is the current platform and will receive hardware-matched feature development for several more years.
Who Should Stay on Gen 3 or Skip Ring 4?
If your Gen 3 is accurate and comfortable, the practical day-to-day difference from upgrading is modest for most users. Sleep scores, HRV trends, and temperature trend data are the metrics most people rely on, and Gen 3 handles these acceptably for the majority of users in sizes 6-13 with typical skin tones.
If cost is the primary concern, a well-priced Gen 3 refurbished unit is still a capable sleep tracking smart ring. The membership cost is identical, so your ongoing monthly cost is the same regardless of which hardware generation you wear.
One practical note: if you are buying a used Gen 3, check that it comes with the original sizing kit and confirm the ring size before buying. Ring sizing is the single biggest complaint among Oura users, and ordering the wrong size on a secondhand purchase leaves you with no recourse.
Whichever ring you use, the data it produces is only as useful as what you do with it. Pairing Oura's overnight metrics with a planning app that schedules your day around your energy levels closes the loop between tracking and action. Lifestack does exactly this: it reads your energy patterns and builds your schedule around them, so that a night of poor sleep or a low HRV reading actually changes how your tasks are timed rather than just being a number you note and forget.
FAQ
Is Oura Ring Gen 3 still sold?
No. Oura discontinued Gen 3 sales from their official store when Ring 4 launched in October 2024. Gen 3 units are available through refurbished sellers and secondhand marketplaces, but they come without Oura's retail warranty.
What is the main difference between Oura Ring 3 and 4?
The primary hardware difference is the sensor platform. Ring 4 uses an 18-path multi-wavelength PPG system (Smart Sensing) compared to Gen 3's narrower sensor array. This improves accuracy for sleep staging, HRV, and respiratory rate, particularly for users where Gen 3 produced inconsistent results. Ring 4 also extends the size range to 4-15 (from Gen 3's 6-13) and improves battery life to up to 8 days.
Can I use my Gen 3 with the new Oura app?
Yes. The current Oura app supports both Ring 4 and Gen 3. Many software features have been backported to Gen 3, including sleep apnea detection and the redesigned app interface. Hardware-dependent features that require Ring 4's sensors will not be available on Gen 3.
Is Ring 4 worth the upgrade from Gen 3?
For most users who are satisfied with their Gen 3 accuracy and comfort, the upgrade is optional rather than urgent. For users who have experienced accuracy issues, struggle with ring sizing, or want to stay on supported hardware long-term, Ring 4 is the right move. The $349 starting price (same membership) is the practical barrier for most people considering the switch.
Does Ring 4 track sleep apnea?
Ring 4 and Gen 3 both support Oura's sleep apnea detection feature through the app. The feature looks for consistent patterns in overnight respiratory rate and blood oxygen data rather than diagnosing individual events. It is a screening signal, not a medical diagnostic tool, and positive signals should be followed up with a clinical sleep study.
What size should I order for Oura Ring 4?
Oura ships a free sizing kit before your ring purchase. Use it over at least 2-3 days and check your finger size at different times of day. Fingers change size with temperature, hydration, and activity. Most people size up one size from what they measure in the morning, as fingers tend to be at their smallest after waking.
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Copyright 2026 © Lifestack. All rights reserved
Copyright 2026 © Lifestack. All rights reserved
