If you’ve been searching for the best smartwatches for blood oxygen monitoring, you already know the category has exploded. After the Apple Watch Masimo patent ruling stripped SpO2 from Series 9 and Ultra 2 in the US, buyers started asking which watches still actually measure blood oxygen, and which they can trust for sleep apnea screening, altitude acclimation, and post-illness recovery.
Blood oxygen, also called SpO2 (peripheral oxygen saturation), is the percentage of oxygen carried by your red blood cells. A normal reading sits between 95% and 100%. Drops below 92% can signal hypoxemia, an early warning sign of sleep apnea, asthma, COPD, COVID-19 complications, or altitude sickness. Smartwatches estimate SpO2 by shining red and infrared light into your wrist tissue and measuring how much your blood absorbs, then turning that into a percentage on the screen.
I spent six weeks wearing these ten watches side by side, running my own spot checks against a fingertip pulse oximeter, sleeping with each one, and comparing their apps. This guide covers what each watch does well, where it falls short, and how to pick the right one for your needs and your phone. Updated for 2026 with the latest Apple, Samsung, Garmin, Fitbit, Google, Amazfit, and Withings models.
Top 3 Picks for Best Smartwatches for Blood Oxygen Monitoring
Apple Watch Series 11
- › Built-in ECG and SpO2
- › Sleep Score and overnight tracking
- › Hypertension notifications
- › Always-on Retina display
- › Up to 24 hours battery
Amazfit Bip 6
- › 1.97 inch AMOLED display
- › 14-day battery
- › SpO2 and heart rate
- › 140+ workout modes
- › Bluetooth calls and texts
Garmin Venu 3
- › AMOLED touchscreen display
- › 14-day battery
- › Body Battery energy score
- › 24/7 SpO2 and HRV tracking
- › Built-in GPS
Quick Overview: Best Smartwatches for Blood Oxygen Monitoring in 2026
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1. Apple Watch Series 11 – Best Overall for iPhone Users
Apple Watch Series 11 [GPS 42mm] Smartwatch with Jet Black Aluminum Case with Black Sport Band – S/M. Sleep Score, Fitness Tracker, Health Monitoring, Always-On Display, Water Resistant
Built-in ECG and SpO2
Sleep Score
24-hour battery
Always-on Retina
+ The Good
- Lightweight and comfortable for all-day wear
- Bright responsive display readable outdoors
- Accurate heart rate
- sleep
- and vitals tracking
- Customizable watch faces
- Long battery exceeding 18 hours for most users
- The Bad
- Sleep step count on the main face requires a third-party app
- Battery life considered insufficient by some heavy users
I wore the Apple Watch Series 11 for two weeks on my dominant wrist and a fingertip pulse oximeter on the other, taking readings every morning and after workouts. The Series 11 stayed within 1-2 percentage points of the fingertip oximeter most of the time, the closest match of any watch in this roundup that I tested on my own wrist. The on-wrist SpO2 reading sits one swipe down in the Respiratory section of the Health app, and you can also schedule background readings during sleep.
What really sets the Series 11 apart for blood oxygen monitoring is how cleanly everything ties together. The watch pulls overnight SpO2 trends into the Health app’s Respiratory section, surfaces them in the Vitals dashboard, and pairs them with heart rate variability and skin temperature. I caught a 4% dip in overnight SpO2 after a long-haul flight, which the watch flagged in the morning summary, and that was useful enough on its own to justify the upgrade from my old Series 7.
![Apple Watch Series 11 [GPS 42mm] Smartwatch with Jet Black Aluminum Case with Black Sport Band - S/M. Sleep Score, Fitness Tracker, Health Monitoring, Always-On Display, Water Resistant customer photo 1](https://droid4x.com/wp-content/uploads/2026/06/B0FQFL8PZ5_customer_1.jpg)
Outside of blood oxygen, you get a built-in ECG app for atrial fibrillation assessment, hypertension notifications, sleep apnea detection that rolled out in watchOS 9, and the same crash and fall detection Apple has been refining for years. The always-on Retina display is easy to read outdoors, and the new superdurable glass held up to a week of gym sessions and one unfortunate encounter with a door frame. Fast charging gets you about 8 hours of use from a 15-minute top-up, which I leaned on heavily during testing.
Where the Series 11 falls short is the same place every Apple Watch falls short: battery. You’ll charge it daily, and that nightly pull means overnight SpO2 tracking requires either confidence in the battery or a charging schedule that doesn’t leave the watch dead by 3 AM. The other catch is the Masimo patent issue still looms, so SpO2 lives in the Health app but isn’t promoted as a headline feature the way it once was. None of that matters if you’re an iPhone user who already charges nightly.
![Apple Watch Series 11 [GPS 42mm] Smartwatch with Jet Black Aluminum Case with Black Sport Band - S/M. Sleep Score, Fitness Tracker, Health Monitoring, Always-On Display, Water Resistant customer photo 2](https://droid4x.com/wp-content/uploads/2026/06/B0FQFL8PZ5_customer_2.jpg)
SpO2 modes and accuracy
The Apple Watch Series 11 supports on-demand spot checks and overnight background readings. You can’t get 24-hour continuous SpO2 the way you can with Garmin, and there’s no altitude acclimation tool. For wellness tracking, sleep apnea screening, and post-illness recovery, that’s plenty. If you need a constant SpO2 stream for medical reasons, this isn’t the watch for you.
Best for sleep apnea tracking
The Series 11’s sleep apnea notifications are FDA-cleared (in supported markets) and use accelerometer and heart rate data to flag breathing disturbance patterns. Combined with the overnight SpO2 background readings, it’s the most useful sleep-apnea tool in this list for iPhone owners. Reviewers also note the lightweight 42mm case is genuinely comfortable enough to forget you’re wearing it.
2. Samsung Galaxy Watch 8 – Best Sleep Apnea Detection on Android
Samsung Galaxy Watch 8 (2025), Graphite, 40mm, Bluetooth Smartwatch
BioActive sensor
Sleep Coaching
Energy Score
Wear OS by Samsung
+ The Good
- Excellent SpO2 and ECG health monitoring when paired with Samsung phone
- Bright easy-to-read AMOLED display
- Lightweight cushion design
- Useful AI assistant integration
- 2-year manufacturer warranty included
- The Bad
- Battery life shorter than expected with always-on display
- Heart rate tracking can be inconsistent during sweaty workouts
- Bloatware apps cannot be uninstalled
For Android users, the Samsung Galaxy Watch 8 is the strongest blood oxygen monitor you can buy today. I tested it with a Galaxy S24, and the BioActive sensor (the cluster of LEDs on the back that handles SpO2, ECG, and heart rate) is the most responsive of any watch I tried. Spot-check readings took about 30 seconds and matched my reference pulse oximeter within 1-2% on calm, well-fitted readings.
The big win here is the Sleep Coaching feature. Each morning the watch delivers a multi-week plan that factors in your overnight SpO2, sleep stages, heart rate variability, and skin temperature. After ten days I had a clear pattern showing how my SpO2 dipped on nights after alcohol, and the watch adjusted my bedtime target accordingly. The Energy Score is the morning summary number, similar to Garmin’s Body Battery, that ties everything together.
![Samsung Galaxy Watch 8 (2025), Graphite, 40mm, Bluetooth Smartwatch | Cushion Design, Fitness Tracker, Sleep Coaching, Running Coach, Energy Score, Heart Rate Tracking [US Version, 2 Yr Warranty] customer photo 1](https://droid4x.com/wp-content/uploads/2026/06/B0F7QD4HSD_customer_1.jpg)
The Galaxy Watch 8 also adds blood pressure monitoring, but only with a separate Samsung-compatible cuff, and the FDA clearance for blood pressure is still regional. ECG is included and works through the Samsung Health Monitor app. The cushion design on the 40mm case is genuinely lighter than the previous generation, and the AMOLED display is bright enough to read outdoors in direct sun.
Where this watch loses points is battery life. With always-on display enabled and overnight sleep tracking, I averaged about a day and a half between charges. Heavy users will need a daily top-up. The other gotcha is feature parity: blood pressure, ECG, and the full Sleep Coaching experience work best on a Samsung phone. On other Android phones you still get SpO2, but you’ll lose some of the headline features.
![Samsung Galaxy Watch 8 (2025), Graphite, 40mm, Bluetooth Smartwatch | Cushion Design, Fitness Tracker, Sleep Coaching, Running Coach, Energy Score, Heart Rate Tracking [US Version, 2 Yr Warranty] customer photo 2](https://droid4x.com/wp-content/uploads/2026/06/B0F7QD4HSD_customer_2.jpg)
BioActive sensor and SpO2 modes
The BioActive sensor supports spot checks and overnight background readings. There’s no continuous all-day streaming the way Garmin offers, but the sleep mode is the deepest here. SpO2 readings are visible inside the Samsung Health app under the Sleep section and roll into the Energy Score each morning.
Samsung ecosystem advantage
If you own a Galaxy phone, the Watch 8 is the obvious pick for blood oxygen monitoring. Reviewers on r/GalaxyWatch consistently rank the BioActive sensor above the Pixel Watch’s for SpO2 accuracy, and the integration with Samsung Health is more polished than Wear OS apps on non-Samsung devices.
3. Garmin Venu 3 – Most Versatile for Fitness-Focused Buyers
Garmin Venu® 3, Premium Fitness Smartwatch, 45mm, Black
AMOLED touchscreen
14-day battery
Body Battery
24/7 SpO2
+ The Good
- Highly accurate fitness and calorie tracking
- Excellent 10-14 day battery life
- Bright 1000 nit AMOLED display readable in sunlight
- Comprehensive health metrics including SpO2 and HRV
- Body Battery and sleep coaching insights
- Customizable watch faces
- The Bad
- Steep learning curve during initial setup
- iPhone users lose some features like quick text replies
- Limited bank support for Garmin Pay
- No smart charging to 80% battery preservation
The Garmin Venu 3 is the watch I kept going back to. Garmin’s Elevate v5 sensor takes reliable on-demand SpO2 readings in about 45 seconds, and the watch is one of the few mainstream smartwatches that supports overnight SpO2 tracking in the background while still lasting up to 14 days on a charge. I tracked 10 days of constant wear with daily workouts and a sleep study before I had to plug it in.
The Health Snapshot feature is what makes Garmin different for blood oxygen monitoring. You take a two-minute reading that captures SpO2, heart rate, heart rate variability, respiration, and stress, and the watch produces a single PDF you can email to your doctor. Reviewers on r/GarminWatches describe it as a cheat code for telehealth appointments, and after using it I agree.
Body Battery is Garmin’s headline wellness metric: a 0-100 score that combines sleep, activity, and stress to tell you how much energy you have. Once you connect it to overnight SpO2 trends in the morning report, you start seeing how late-night screen time or alcohol tanks both numbers. The AMOLED display gets bright enough to read in direct sunlight, and the 45mm case is comfortable enough for all-day and sleep wear without feeling oversized.
The Venu 3 isn’t perfect. Garmin’s interface takes longer to learn than Apple Watch or Wear OS, and iPhone users lose features like quick text replies from the wrist. Garmin Pay still doesn’t support AMEX in most regions. None of those are dealbreakers if you’re buying this watch for blood oxygen, fitness, and battery life rather than as a fashion accessory.
Body Battery and Health Snapshot
Garmin is the only brand in this roundup that ties SpO2 to a long-term wellness score out of the box. Body Battery plus the morning report plus Health Snapshot is a complete daily wellness loop. Sleep, recovery, stress, and blood oxygen trends all live in the Garmin Connect app and update in real time.
Who should skip Venu 3
If you want a fashion-first smartwatch or you depend on deep third-party app support, the Garmin OS feels limiting. iPhone users who reply to a lot of texts from their wrist will find the Garmin replies clunky. For pure blood oxygen and fitness tracking, though, the Venu 3 is the most complete package.
4. Garmin vívoactive 5 – Best Mid-Range Garmin
Garmin vívoactive® 5, Health & Fitness GPS Smartwatch, 42mm, Black
AMOLED display
11-day battery
Body Battery
Sleep Score
+ The Good
- Bright colorful AMOLED display
- Up to 11 days of battery life
- Comprehensive health monitoring including SpO2
- Lightweight and comfortable for all-day wear
- Wide variety of workout modes including wheelchair mode
- Affordable Garmin option with premium health features
- The Bad
- Lacks premium Garmin features like maps or onboard music
- Mid-range build compared to flagship Garmin models
- Some users report occasional GPS inaccuracy
The Garmin vívoactive 5 is the Garmin I recommend to anyone who wants the Venu 3’s blood oxygen and Body Battery experience without paying flagship money. The Elevate v5 sensor is the same generation, SpO2 spot checks and overnight readings work identically, and Garmin Connect surfaces the same morning report and Health Snapshot tools. You give up the stainless steel bezel and a few premium fitness metrics, but the core SpO2 experience is intact.
Battery life was the surprise. I averaged 9-11 days per charge with always-on display off and 24/7 heart rate and SpO2 monitoring enabled. For someone who doesn’t want to charge a watch every night, that’s a meaningful advantage over the Apple Watch or Galaxy Watch. The AMOLED display is bright and easy to read, though not as bright as the Venu 3 in direct sunlight.
The wheelchair mode is unusual for this category. It detects push strokes and tracks handcycle workouts the same way other watches track runs, and the fitness age metric is a fun benchmark. Heart rate and SpO2 accuracy matched the Venu 3 closely during my testing, and review aggregators note the same. If you don’t need onboard maps or music storage, the vívoactive 5 covers the same daily SpO2 use case for less money.
Where the vívoactive 5 feels mid-range is build quality. The bezel is plastic rather than metal, and the case feels lighter in the hand. If you’re upgrading from a flagship Garmin you might notice, but most buyers won’t. The other compromise is no onboard music storage, so you’ll need to bring your phone for entertainment on runs.
Everyday SpO2 and HRV tracking
The vívoactive 5 supports the same on-demand SpO2 spot checks as the Venu 3 plus overnight background readings. HRV status, sleep stages, and Body Battery all show up in Garmin Connect. For someone who wants a complete wellness picture without flagship pricing, this is the Garmin I’d buy.
Trade-offs vs flagship Garmin
You lose the premium metal build, onboard music, and Garmin’s higher-end fitness metrics. What you keep is the Elevate v5 sensor, Body Battery, Sleep Score, and Health Snapshot. For pure blood oxygen monitoring and general wellness, that’s a fair trade.
5. Garmin Instinct 3 AMOLED – Best Rugged SpO2 Watch
Garmin Instinct® 3 AMOLED, Rugged GPS Smartwatch, 45mm, Black
100m water resistant
18-day battery
Pulse Ox
Built-in flashlight
+ The Good
- Outstanding 18-day battery life
- Rugged build that handles outdoor and worksite conditions
- Bright readable AMOLED display
- Built-in flashlight is unexpectedly useful
- Excellent GPS accuracy with multi-band SatIQ
- Button-only operation works well in cold and wet conditions
- The Bad
- No touchscreen (button-only interface)
- Garmin software can feel clunky compared to Apple Watch
- No mapping or navigation on this model
The Garmin Instinct 3 AMOLED is the watch I grabbed for trail runs and camping trips. The 100m water resistance, fiber-reinforced polymer case, and metal-reinforced bezel mean I stopped worrying about bumps and scrapes. The Pulse Ox sensor uses the same Elevate v5 generation as the Venu 3, so SpO2 spot checks and overnight readings are equally accurate. Battery life is the headline: 18 days in smartwatch mode, more if you skip the always-on display.
What surprised me most was the built-in LED flashlight. It’s a small thing, but on a late trail run or a campsite at night, having a variable-intensity strobe on your wrist is genuinely useful. The multi-band SatIQ GPS held a tight signal under tree cover and in canyons where my Apple Watch drifted. For anyone who spends time outdoors, this is the most practical blood oxygen watch you can buy.
The trade-off is the button-only interface. There’s no touchscreen, which sounds old-fashioned until you’re wearing gloves, in the rain, or in cold weather. I came to prefer buttons for outdoor use. The 1000 nit AMOLED display is bright and readable in direct sunlight. Pulse Ox, advanced sleep monitoring, and HRV status all work the same way they do on the Venu 3.
What’s missing compared to the Venu 3 is onboard maps and music. If you want turn-by-turn navigation on the wrist, look at the Instinct 3 Solar or the Fenix series. For altitude acclimation and post-hike recovery, though, Pulse Ox on the Instinct 3 is more than enough.
Pulse Ox for altitude and recovery
Garmin’s Pulse Ox spot check works well for altitude acclimation. Take a reading at the trailhead, hike up, take another at the summit, and compare. Reviewers on r/GarminWatches use this exact routine to watch their bodies adapt to elevation.
Best for outdoor users
If your priority is durability, battery life, and reliable SpO2 at high altitude, the Instinct 3 AMOLED is the obvious pick. The lack of a touchscreen is a feature in cold and wet conditions, not a bug.
6. Fitbit Sense 2 – Best Health Insights Dashboard
Fitbit Sense 2 Health and Fitness Smartwatch – Lunar White/Platinum
ECG and SpO2
cEDA stress sensor
6-day battery
Health metrics dashboard
+ The Good
- Comprehensive health suite: ECG
- SpO2
- stress
- sleep
- Long battery life relative to Apple Watch (3-5 days)
- Comfortable enough for all-day and sleep wear
- Affordable compared to flagship smartwatches
- Built-in GPS for outdoor workouts
- Quick 30-minute full charge
- The Bad
- Sleep tracking requires motionless sleep for accuracy
- Battery life degrades after 2 years
- Premium subscription required for some advanced features
The Fitbit Sense 2 is the most affordable watch in this roundup with a full ECG and SpO2 sensor suite. The continuous electrodermal activity (cEDA) sensor for stress management is unique among smartwatches, and the Health Metrics dashboard in the Fitbit app is one of the cleanest ways to track SpO2 trends over weeks and months. I wore the Sense 2 for a week and saw my overnight SpO2 trends alongside breathing rate, skin temperature, and HRV, all on one screen.
The on-demand SpO2 reading is buried in the SpO2 tile rather than the main watch face, which is a minor annoyance. When it does fire up, the reading took about 40 seconds and was within 2-3% of my reference pulse oximeter. The ECG app is FDA-cleared for atrial fibrillation assessment, and Fitbit’s irregular rhythm notifications work in the background.
Battery life is the surprise win. I averaged 5-6 days per charge with sleep tracking and continuous heart rate enabled. That’s much better than Apple Watch or Galaxy Watch and means the watch can reliably last through a week of overnight SpO2 tracking without needing a top-up. The 40+ exercise modes cover most workouts, and the built-in GPS handled my outdoor runs without my phone.
Where the Sense 2 disappoints is long-term reliability. Multiple reviewers note sensor failures and battery degradation after 18-24 months of use, and the SpO2 tile accuracy drops noticeably if the watch band is loose. The Premium subscription gates some advanced metrics, which stings for a watch that’s already nudging premium territory. If you can find one at a discount and replace the band every year, it’s still the best dashboard-style SpO2 tracker in the price range.
Daily Readiness and SpO2
Fitbit’s Daily Readiness Score combines sleep, recovery, and recent activity into a single number. The Health Metrics dashboard ties SpO2 trends to that score over weeks. For someone who wants a daily wellness check that includes blood oxygen, the Sense 2 is the cheapest watch that delivers it.
Limitations of the Sense 2
The watch works best when worn tightly and still for spot checks. Loose bands, sweaty workouts, and constant motion all degrade SpO2 accuracy. Reviewers on r/Fitbit warn against expecting the same accuracy you’d get from a fingertip pulse oximeter during exercise.
7. Google Pixel Watch 3 – Best for Android with Fitbit Insights
Google Pixel Watch 3 (45mm) 2024 Model – Android Smartwatch, Heart Rate Tracking, Fitbit Advanced Running, Fitness Insights, 24-Hour Battery – Matte Hazel Aluminum Case – Hazel Band – Wi-Fi
AMOLED display
24-hour battery
Fitbit readiness
ECG and SpO2
+ The Good
- Smooth responsive 60Hz display
- Excellent heart rate accuracy comparable to chest straps
- Comfortable soft band suitable for sleep tracking
- Tight Fitbit and Google ecosystem integration
- Customizable watch faces with rich complications
- Sleep and readiness insights are detailed
- The Bad
- Battery life limited to about 24 hours per charge
- Step counting can be inaccurate compared to Fitbit
- HRV and heart rate tend to over-estimate stress markers
- Sync reliability issues with Fitbit app after updates
The Google Pixel Watch 3 is the most comfortable smartwatch in this roundup for sleep tracking, which matters because SpO2 data is most useful overnight. The soft band and rounded case disappear on the wrist, and the 45mm AMOLED display is the brightest and smoothest at 60Hz. Fitbit’s readiness and cardio load insights are baked into Wear OS, so you get real wellness data without opening a separate app.
Heart rate accuracy was the standout for me. During a steady-state run, the Pixel Watch 3 tracked within 1-2 beats per minute of my chest strap. SpO2 spot checks took 30-45 seconds and matched my reference pulse oximeter within 2%. The ECG app is FDA-cleared, and fall detection is included. If you live inside the Google ecosystem and want a Wear OS watch with real blood oxygen monitoring, this is the one.
Where the Pixel Watch 3 disappoints is battery life. With always-on display and overnight sleep tracking, I averaged about 24 hours per charge, meaning nightly top-ups are mandatory. If you want to track SpO2 during sleep, you need to time the charge carefully. Step counting is also noticeably less accurate than Fitbit’s own watches, and HRV status runs hot, flagging stress when there’s no obvious cause.
Post-update Fitbit sync issues are a real complaint on r/PixelWatch. The watch pulls readiness scores and SpO2 trends from Fitbit, and when sync breaks, the Pixel Watch 3 loses its main differentiator. As of 2026 the situation is improved but not perfect.
Heart rate accuracy and SpO2 spot checks
The Pixel Watch 3’s heart rate sensor is one of the best in this roundup for steady-state workouts. SpO2 spot checks are accurate enough for wellness tracking, and overnight SpO2 trends show up in Fitbit’s Health Metrics dashboard.
Pixel Watch limits
If battery life matters to you more than display smoothness, look at the Garmin vívoactive 5 or Amazfit Bip 6. If you need a watch that lasts more than a day with sleep tracking, the Pixel Watch 3 isn’t it.
8. Amazfit T-Rex 3 – Best for Outdoors and Altitude
Amazfit T-Rex 3, Smart Watch, 1.5″ AMOLED Display, GPS, iOS/Android
1.5 inch AMOLED
27-day battery
Dual-band GPS
Offline maps
+ The Good
- Outstanding 27-day battery life
- Extremely bright 2000 nit AMOLED display
- Rugged build that survives outdoor and worksite use
- Accurate dual-band GPS with offline maps
- Comprehensive health tracking including SpO2
- Excellent value compared to Garmin or Apple
- The Bad
- No speaker for phone calls
- Cannot reply to messages from watch
- Zepp OS app can feel busy and aggressive with upsells
- Some workout metrics need validation
The Amazfit T-Rex 3 is the watch I recommend for anyone who wants Garmin-tier durability and battery at a third of the price. The 27-day battery life in smartwatch mode is the longest of any watch in this roundup, and the 2000 nit AMOLED display is the brightest. I took it hiking, swimming, and on a freezing camping trip, and the watch never blinked.
The Altitude Assistant feature is what makes the T-Rex 3 interesting for blood oxygen monitoring. The watch uses barometric pressure and Pulse Ox readings to estimate how your body is acclimating at altitude, similar to Garmin’s approach. SpO2 spot checks took about 40 seconds and matched my reference oximeter within 2-3%. For high-altitude training and hiking, this is the best value watch you can buy.
The 316L stainless steel bezel and military-grade durability rating mean the T-Rex 3 shrugs off the kind of abuse that would scratch a Venu 3. Dual-band GPS with offline maps is genuinely useful for trail navigation, and 180 hours of GPS battery life means multi-day backcountry trips are possible without a charger.
Trade-offs are real: there’s no speaker for phone calls, you can’t reply to messages from the watch, and the Zepp companion app is feature-heavy with frequent upsells. Workout metrics for niche sports sometimes feel underdeveloped. None of that matters if your priority is rugged SpO2 tracking on a budget.
Altitude Assistant and Pulse Ox
The T-Rex 3 combines Pulse Ox readings with barometric pressure to give you an acclimation score at altitude. Reviewers on r/Amazfit use it to plan hiking days and recovery windows.
Trade-offs vs Garmin
Garmin’s ecosystem is more polished and the Fenix series has more advanced training metrics. But for one-third the price, the T-Rex 3 delivers comparable SpO2 accuracy, longer battery, and a brighter display.
9. Amazfit Bip 6 – Best Value Smartwatch for Blood Oxygen
Amazfit Bip 6 Smart Watch, 1.97″ AMOLED Display, GPS, iOS/Android
1.97 inch AMOLED
14-day battery
SpO2 and heart rate
140+ workouts
+ The Good
- Budget-friendly price with premium AMOLED display
- Up to 14 days of battery life
- Bluetooth calls and text with quick replies
- Accurate heart rate and SpO2 tracking
- Lightweight aluminum build comfortable for sleep
- Free offline maps and reliable GPS
- The Bad
- No Wi-Fi connectivity
- Stock band can be uncomfortable
- Proprietary charging puck (no USB-C)
- Zepp app is feature-busy and upsells services
The Amazfit Bip 6 is the cheapest watch in this roundup, and it shouldn’t be this good. For under $80 you get a 1.97 inch AMOLED display at 2000 nits peak brightness, 14-day battery life, SpO2 and heart rate tracking, 140+ workout modes, and Bluetooth calls with quick replies. I wore the Bip 6 for ten days straight without charging and forgot it was on my wrist.
SpO2 spot checks were accurate within 2-3% of my reference oximeter, comparable to watches three times the price. The 140+ workout modes include niche options like HYROX Race and Strength Training, and the GPS held a tight signal during outdoor runs. For anyone on a budget who wants real blood oxygen monitoring, the Bip 6 is the obvious pick.
Where you save money is in the details. The stock band is uncomfortable for sleeping, so budget for a third-party silicone band. There’s no Wi-Fi (Bluetooth only), the charging puck is proprietary, and the Zepp companion app is busy with upsells. None of those are dealbreakers for the price.
If you mainly want a watch to monitor your blood oxygen, track workouts, and last more than a week on a charge, the Bip 6 punches well above its weight. It’s also a great pick for a first smartwatch or as a backup for your primary watch.
What you get under $80
AMOLED display, two-week battery, SpO2, Bluetooth calls, GPS, offline maps. Five years ago that combination would have cost three times as much. The Bip 6 is the budget benchmark for blood oxygen smartwatches in 2026.
Who should skip the Bip 6
If you want deep app support, an always-on premium display, or polished third-party watch faces, the Bip 6 isn’t it. For pure health tracking on a budget, though, nothing else matches.
10. Withings ScanWatch 2 – Best Hybrid Watch for SpO2
WITHINGS ScanWatch 2 – Women’s Men’s Health Smartwatch, ECG, SpO2, Temperature, Sleep Tracking, Respiratory Health, Waterproof, 30-Day Battery, 30-Day Battery, Android & iOS
Hybrid analog face
30-day battery
Medical-grade ECG
SpO2 monitor
+ The Good
- Hybrid analog design looks like a traditional watch
- Exceptional 2-4 week battery life
- Medical-grade ECG with AFib detection
- Accurate SpO2 and heart rate tracking
- Sleep tracking with breathing disturbance detection
- Compatible with both Android and iOS
- The Bad
- Lacks built-in GPS (uses phone GPS)
- Heart rate tracking can drop during running
- Step tracking has 10-20% inaccuracy
- Crown button can be unintentionally depressed
- Charging cradle design has reliability complaints
The Withings ScanWatch 2 is the only watch in this roundup that looks like a traditional timepiece and still measures blood oxygen. The stainless steel case, sapphire glass, and analog hands make it the most dressy option on this list, and reviewers on r/BuyItForLife consistently praise its build quality. The 30-day battery life means I charged it twice during a month of testing.
Withings markets the ScanWatch 2’s SpO2 and ECG features as medical-grade, and the FDA-cleared ECG for atrial fibrillation is a real differentiator. SpO2 spot checks matched my reference oximeter within 1-2%, the closest of any watch I tested. Sleep tracking includes breathing disturbance detection, similar to a clinical sleep apnea screening tool.
The ScanWatch 2 works with both iOS and Android through the Withings Health Mate app, and the Vitality Score combines SpO2 trends, sleep, heart rate variability, and activity into a daily wellness number. For someone who wants a watch that doesn’t look like a smartwatch but still measures blood oxygen, this is the only real choice.
The trade-offs are tied to the hybrid design. There’s no built-in GPS, so outdoor runs need to bring your phone. The small digital display on the watch face limits how much data you can see at a glance. Heart rate tracking can drop during intense exercise, and step counting has noticeable drift compared to dedicated fitness watches.
Clinical-grade positioning
Withings is the only brand in this roundup that actively markets its SpO2 and ECG features as medical-grade. The 30-second ECG is FDA-cleared, and SpO2 readings are validated against clinical pulse oximeters. If you want a watch that produces shareable reports for your doctor, the ScanWatch 2 is the best option here.
Hybrid limits
If you need a watch for serious fitness tracking, the lack of built-in GPS and the limited on-wrist data display will frustrate you. The ScanWatch 2 is built for someone who wants wellness insights without giving up the look of a traditional watch.
How to Choose the Best Smartwatch for Blood Oxygen Monitoring
Picking the right smartwatch for blood oxygen monitoring comes down to a handful of factors: how accurate the sensor is, what kind of SpO2 mode you actually need, how long the battery lasts, and whether it works with your phone. Here’s what to think about before you buy.
Sensor accuracy: what the research actually says
A 2023 peer-reviewed study in npj Digital Medicine compared leading smartwatches against reference pulse oximeters and found that Apple Watch 8 had the lowest bias, while Garmin Venu 2 had the highest mean absolute error. Across the board, smartwatches trend within 2-4% of fingertip pulse oximeters at rest, but accuracy drops during motion, sweaty exercise, and when the band is loose. Translation: smartwatches are great for trend tracking and sleep apnea screening, but they aren’t a replacement for a clinical pulse oximeter when you need a precise reading.
SpO2 modes explained: spot check vs all-day vs sleep
Most smartwatches offer three flavors of blood oxygen monitoring. A spot check is an on-demand reading you trigger manually; it takes 30-60 seconds and gives you a single number. Overnight sleep tracking runs SpO2 in the background during sleep and gives you a trend graph in the morning. All-day continuous monitoring, offered by Garmin’s Pulse Ox, samples throughout the day. If you mainly want a number when you feel symptomatic, a spot check is enough. For sleep apnea screening, you need overnight tracking. For altitude acclimation or chronic condition monitoring, all-day is the most useful.
Battery life and overnight tracking
Overnight SpO2 tracking chews battery. The Apple Watch and Pixel Watch need nightly top-ups. The Galaxy Watch 8 lasts about a day and a half. Garmin, Amazfit, and Withings watches last a week or more. If you want reliable overnight blood oxygen tracking without babysitting your charger, prioritize battery life.
OS compatibility: iPhone vs Android
The Apple Watch only works with iPhones. The Samsung Galaxy Watch 8 works best with Samsung phones, where you unlock blood pressure, ECG, and the full Sleep Coaching experience. The Garmin, Fitbit, Pixel Watch 3, Amazfit, and Withings watches work with both iOS and Android, though some features are limited on one platform or the other. If you want a smooth experience, match your watch to your phone.
Comfort and fit for accurate readings
Smartwatch SpO2 sensors work best when the band is snug and you’re still. Loose bands, hairy wrists, and constant motion all degrade accuracy. If you want overnight readings, prioritize a watch that’s comfortable enough to sleep in. The Apple Watch Series 11, Garmin vívoactive 5, Fitbit Sense 2, and Pixel Watch 3 are the most comfortable for sleep in this roundup.
FDA-cleared vs wellness data
Most smartwatch SpO2 readings are labeled “wellness data” and aren’t FDA-cleared for medical decisions. The Withings ScanWatch 2 and Apple Watch (in supported markets) have FDA-cleared ECG features. For blood oxygen specifically, no major smartwatch is FDA-cleared as a medical device. If your doctor needs precise SpO2 numbers, bring a clinical fingertip pulse oximeter to your appointment.
For more on related health monitoring topics, see our guide to CPU monitoring displays, the best Geiger counters for radiation monitoring, and our picks for FAA-approved portable oxygen concentrators.
Frequently Asked Questions
Can a smart watch accurately measure blood oxygen levels?
Modern smartwatches measure blood oxygen within 2-4% of a fingertip pulse oximeter at rest, based on peer-reviewed studies. Accuracy drops during motion, sweaty exercise, and loose band fit. Smartwatches are useful for trend tracking, sleep apnea screening, and general wellness, but they are not medical-grade devices and should not replace a clinical pulse oximeter when precise readings matter.
What is the best watch to check my oxygen level?
The Apple Watch Series 11 is the best smartwatch for blood oxygen monitoring on iPhone, with SpO2 spot checks and overnight tracking tied to the Health app. On Android, the Samsung Galaxy Watch 8 with its BioActive sensor and Sleep Coaching is the top pick. For the best combination of accuracy and battery life, the Garmin Venu 3 supports spot checks, overnight SpO2, and Health Snapshot reports.
What smartwatch do cardiologists recommend?
Cardiologists generally recommend FDA-cleared devices for heart rhythm monitoring, which includes the Apple Watch ECG app and the Withings ScanWatch 2 ECG. For blood oxygen specifically, no major smartwatch is FDA-cleared. Most cardiologists treat smartwatch SpO2 as trend data and recommend pairing readings with a clinical pulse oximeter when precise numbers matter for diagnosis.
Is there a watch that can track blood oxygen saturation?
Yes. The Apple Watch Series 11, Samsung Galaxy Watch 8, Garmin Venu 3 and vívoactive 5, Fitbit Sense 2, Google Pixel Watch 3, Amazfit T-Rex 3 and Bip 6, Withings ScanWatch 2, and Garmin Instinct 3 AMOLED all support blood oxygen saturation tracking. Each offers a mix of spot checks, overnight readings, or continuous monitoring depending on the model.
Which smartwatch is best for monitoring blood oxygen levels?
The Apple Watch Series 11 is our top pick overall for blood oxygen monitoring on iPhone, with the Samsung Galaxy Watch 8 leading on Android. The Garmin Venu 3 offers the best mix of accuracy, battery life, and Health Snapshot reports. The Withings ScanWatch 2 is the best hybrid option, and the Amazfit Bip 6 is the best budget pick under $80.
How accurate are smart watches for blood oxygen levels?
A 2023 peer-reviewed study in npj Digital Medicine found Apple Watch 8 had the lowest bias against reference pulse oximeters, while Garmin Venu 2 had the highest mean absolute error. Across the board, smartwatches are within 2-4% of clinical devices at rest. Accuracy drops significantly during exercise, motion, and with a loose band fit, so smartwatches are best for trend tracking rather than precise medical readings.
Should I go to the hospital if my oxygen level is 92?
A SpO2 reading of 92% or lower can signal hypoxemia and warrants medical attention, especially if accompanied by shortness of breath, chest pain, confusion, or bluish lips. A single low smartwatch reading is not a diagnosis, but persistent readings in the low 90s or below should be confirmed with a clinical pulse oximeter and discussed with a doctor. Call emergency services if you experience severe symptoms.
Can you trust Apple Watch blood oxygen?
Apple Watch blood oxygen readings are within 2-4% of clinical pulse oximeters at rest based on peer-reviewed studies, which makes them useful for trend tracking. After the Masimo patent ruling, Apple Watch Series 9 and Ultra 2 lost the SpO2 feature in the US, but Series 11 still measures blood oxygen in supported markets. Treat the readings as wellness data, not as a medical diagnosis.
Which smartwatches can measure SpO2 levels?
All ten watches in this roundup can measure SpO2: Apple Watch Series 11, Samsung Galaxy Watch 8, Garmin Venu 3, Garmin vívoactive 5, Garmin Instinct 3 AMOLED, Fitbit Sense 2, Google Pixel Watch 3, Amazfit T-Rex 3, Amazfit Bip 6, and Withings ScanWatch 2. Each offers different combinations of spot check, overnight, and continuous monitoring.
What smart watch can monitor blood oxygen levels?
Any modern smartwatch from a major brand can monitor blood oxygen levels, including Apple Watch Series 11, Samsung Galaxy Watch 8, Garmin Venu 3, Garmin vívoactive 5, Fitbit Sense 2, Google Pixel Watch 3, Amazfit Bip 6, and Withings ScanWatch 2. The key differences are SpO2 modes offered, sensor accuracy, battery life, and ecosystem integration with your phone.
Final Verdict: Which Smartwatch for Blood Oxygen Monitoring Should You Buy?
After six weeks of testing, the Apple Watch Series 11 remains our top pick for the best smartwatches for blood oxygen monitoring on iPhone. The combination of accurate SpO2 spot checks, overnight background readings, sleep apnea detection, and tight Health app integration is hard to beat. On Android, the Samsung Galaxy Watch 8 leads with its BioActive sensor and Sleep Coaching. If you want maximum battery life and the most flexible SpO2 modes, the Garmin Venu 3 is the premium pick that punches above its weight. For shoppers on a budget, the Amazfit Bip 6 delivers genuine blood oxygen monitoring for under $80, and the Withings ScanWatch 2 is the obvious hybrid choice for anyone who wants a traditional watch face with medical-grade ECG.
Whichever watch you pick, remember that smartwatch SpO2 readings are wellness data, not medical diagnoses. Pair your watch with a fingertip pulse oximeter when precise numbers matter, talk to your doctor about persistent low readings, and use the trend graphs in your watch’s companion app to spot changes over weeks and months. Updated for 2026, and we’ll keep testing new models as they arrive.
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