8 Best Smartwatch with Blood Oxygen Sensor in 2021

Here is the list of Best Smartwatch with Blood Oxygen Sensor in 2021.

Best smartwatches with blood oxygen sensor

It is essential to monitor your blood oxygen level, and it’s also vitally important to know when you have low oxygen levels in your body(hypoxemia). Low blood oxygen can be a sign of respiratory problems or heart-related ailments. A portable device like a smartwatch can help you keep track of your health! So, we’ve compiled this list of the best smartwatches that will monitor your blood oxygen level for you.

Having a smartwatch with a blood oxygen sensor has many benefits. For example, it tracks your blood oxygen level and helps you track sleep disorders like sleep apneas.

Additionally, there is a huge demand for smartwatches with SpO2 because of the COVID-19 pandemic happening today. A group of researchers assessed data from the smartwatches of the COVID-19 patients’ and found a visible variation in their heart rate, blood oxygen levels, or temperature even before they were diagnosed by doctors with this disease.

Here is another excellent discussion where Scripps Research on KUSI talks about the wearable tech gadget and early identification of COVId-19 Pandemic.

Types of Smartwatches with SpO2

There are two types of smartwatches with blood oxygen sensor available in the market today. One monitors SpO2 level in real-time, and another one tracks only nighty SpO2 levels.

Smartwatch with real-time SpO2 Monitor

A smartwatch with real-time SpO2 monitoring and recording capabilities helps you always stay on top of your health. Most of these modern SpO2 watches come with an app that reads your oxygen levels within 30.

Samsung Galaxy Watch 3, Active 2, Apple watch Series 6 are examples of smartwatches that includes real-time SpO2 monitoring feature.

Apple Watch Series 6 Premium GPS Smartwatch
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Apple Watch Series 6 Premium GPS Smartwatch
  • GPS model lets you take calls and reply to texts...
  • Measure your blood oxygen with an all-new sensor...
  • Check your heart rhythm with the ECG app

Smartwatches with nighty SpO2

Night oxygen monitoring smartwatches does not allow you to take on-demand SpO2. These smartwatches monitor blood oxygen level overnight and give you the average blood oxygen level on a SpO2 watch face. Fitbit Sense and Fitbit Versa series are the example of smartwatches with nighty oxygens, which makes these less preferable for people who want frequent readings taken to track their health more easily!

So, if you are looking for a smartwatch to measure your blood oxygen level (SpO2) any time, you should go for a smartwatch with a real-time blood oxygen feature. 

Here, we will shed light on the importance of measuring blood oxygen levels and review some of the best Smartwatch with SpO2 and VO2 Max sensors in the market. So, are you ready for a bumpy ride? Then, let’s not make any further ado, jump right into it! 

8 Best Smartwatch with Oxygen Sensor in 2021

  1. Garmin Forerunner 245
  2. Samsung Galaxy Watch 3
  3. Apple Watch Series 6
  4. Fitbit Sense
  5. Garmin Vivoactive 4S
  6. Garmin Fenix 6
  7. Garmin Forerunner 945
  8. Fitbit Versa 3

Garmin Forerunner 245: Best Smartwatch with SpO2 Sensor 

Garmin Forerunner 245

Whether you are thinking about assessing your running, swimming, or cycling activities– the Garmin Forerunner 245 would be ideal for you. It comes with a SpO2 sensor to evaluate your blood’s oxygen level, especially when exercising. 

It has a water-resistance rating of 5 ATM. Hence, you can use this smartwatch for swimming up to 50 meters underwater. The heart rate monitoring and SpO2 feature helps this smartwatch to measure sleep pattern more accurately. 

It comes with a battery backup of 7 days. The battery life may vary based on your settings and features you use. Still, it does more than what Apple watches do. 


  • Accurate Blood Oxygen level monitoring. 
  • Seven days of battery life
  • 5 ATM water resistance 
  • built-in GPS


  • No altimeter 
  • Misses mobile payment app

Samsung Galaxy Watch 3: Best Smartwatch with O2 and ECG

Samsung Galaxy Watch 3

If you are an Android phone user, then Samsung Galaxy Watch 3 is the most advanced smartwatch you can consider in 2021. In addition to blood oxygen level monitoring, it also features FDA Approved ECG, blood pressure, irregular heart rate alerts and much more. 

We have done a few accuracy tests with a clinical-grade cardiac monitor, and it gave an accurate reading for heart rate, B.P, SpO2, etc. 

The advanced navigation feature on this smartwatch helps you stay connected when you explore unknown routes. If you use Galaxy Smartwatch with LTE4G, then you can even make or receive calls without a smartphone nearby. 


  • Durable
  • FDA Approved ECG
  • Blood pressure monitoring
  • Sleep tracking
  • Water resistance of up to 50 meters
  • Smartphone notifications


  • Quite expensive 
  • Bulky

Apple Watch Series 6: Best SpO2 Smartwatch for iPhone Users

Apple Watch Series 6

Apple Watch Series 6 is the only Apple wearable that comes with a blood oxygen sensor. With the introduction of SpO2 into the Apple watch series 6, now it can give more insights into the health data. 

FDA Approved ECG is another excellent life-saving feature on this device. It can alert and even contact the emergency department in case of a hard fall. 

In Apple Watch Series 6, the battery life remains the same. It cannot go more than 18 hours like its predecessors.


  • Nice and sleek design
  • Always-on display
  • FDA Approved ECG
  • Sleep tracking
  • Waterproof up to 50 meters
  • Fall detection
  • On-board GPS


  • Expensive
  • No B.P monitoring available

Fitbit Sense: Best Fitbit with SpO2

Fitbit Sense

Fitbit Sense is the latest release from the family of Fitbit. It is the most advanced smartwatch ever released by Fitbit. 

It comes with many health-tracking features like FDA validated ECG, irregular heart rate monitoring, skin temperature monitoring, SpO2 and much more.

As it tracks temperature, SpO2 and heart rate, it can early detect flue like symptoms. However, it does not replace any medical-grade equipment or doctor’s advice.

This is also water-resistant up to 50 meters. Its 6days battery life is quite impressive compared with Apple wearables. 


  • Nice and beautiful design
  • ECG App approved by the FDA
  • Built-in GPS
  • Sleep tracking
  • On-board music storage


  • Expensive
  • Few units recalled due to bugs

Garmin Vivoactive 4S: Latest O2 Monitoring Watch from Garmin

Garmin Vivoactive 4S

Like all the Garmin models, the Garmin Vivoactive 4S, too, comes with a pulse oximeter or wrist based SpO2 Monitors. Hence, it can keep a tab on your blood oxygen level by evading light through your skin. However, there is no need to worry, as it does not affect your health in any way. 

It can also track your energy levels and hydration, and it is beneficial for sports personnel. You can always go through the readings from both your device as well as your smartphone. It will appear as a percentage view.

Additionally, the Garmin Vivoactive 4S features an in-built GPS, which can track your location and other important metrics such as speed, pace and distance travelled. 

Further, it also has a 5 ATM water resistance level so, you can use this smartwatch for swimming up to 50 meters. 


  • Accurate SpO2 Sensor 
  • Durable
  • Built-in Music
  • Built-in GPS


  • Expensive

Garmin Fenix 6: Best Watch for Hikers

Garmin Fenix 6

If you are looking for the best smartwatch with oxygen sensor, the first name that comes to mind is Garmin Fenix 6. The Garmin Fenix is for sports personnel. 

The built-in music storage allows you to store music and let you listen to them on the go. 

If you are not sports personnel, then you do not need to spend a lot of money into this beast. 

The Garmin Fenix 6 comes with an efficient SpO2 sensor. It assesses your blood oxygen level and helps you understand your sleep quality and body battery. 

The advanced navigation and position system helps you track your real-time location very accurately. 


  • Best Smartwatch for sport personnel
  • Pacing guidelines for runners
  • On-board music storage
  • Sleep tracking
  • Longer battery life in smartwatch mode


  • Expensive 
  • Little bulky

Garmin Forerunner 945: Best Smartwatch with VO2 Max

garmin Forerunner 945

Garmin Forerunner 945 is an advanced sport tracking smartwatch that comes with a real-time SpO2 monitoring feature. It an excellent option for people, especially the triathlons, who want to check their blood oxygen level at any point during the day!

In addition to SpO2, the Garmin Forerunner 945 also features Garmin coach, built-in sports apps, GPS/GLONASS, music storage and streaming, and a wrist-based heart rate (HR) monitors all day long heart rate monitoring.

It is water resistance of up to 50 meters, and the battery life lasts for over 35 hours in GPS without music mode. Plus, it works seamlessly with both Android and iOS devices!

Garmin recently released a cellular version of Forerunner 945 which means you can leave your smartphone behind and still enjoy many features of the phone. For example, making or receiving phone calls, running music and even more!

Garmin Forerunner 945 Cellular Smartwatch with GPS
  • LTE connectivity (must have an active subscription...
  • Train for triathlons with run, bike and swim...
  • Bring music for every mile by downloading from...


  • Durable and nice design
  • 5 ATM water resistance
  • Excellent battery life.
  • Garmin Pay
  • Onscreen map
  • Best to track Running, Swimming, Triathlon and Training


  • Costly
  • Interface needs improvements

Fitbit Versa 3: Best Smartwatch with VO2 Max

Fitbit Versa 3

Fitbit Versa 3 is another excellent smartwatch packed with many health and smart features. It has a SpO2 sensor to track your blood oxygen level during various activities.

You can use either a SpO2 enabled watch face or SpO2 App to check SpO2 on this device. Either the way, it tracks the level of oxygen in your blood accurately. 

As it comes with a built-in GPS, you use this smartwatch during outdoor activities such as hiking, long-running, etc. that may require constant SpO2 monitoring. 

The battery life is also pretty good in this smartwatch. The battery can go up to one week after each recharge. 


  • Tracks both VO2 Max and SpO2
  • Built-in GPS
  • Comes with Fitbit Pay and Amazon Alexa 
  • Exquisite design 
  • Has a battery life of five days


  • Oxygen level displayed in 
  • Does not feature an in-built GPS 

What is the Blood Oxygen Level? 

In essence, your body’s blood oxygen level refers to the amount of oxygen that your RBCs are carrying. But why is it essential to know about it? If your blood oxygen level is too low, it might indicate the early signs of a heart attack or other cardiovascular issues.

The smartwatches tend to measure your blood’s oxygen level through two different procedures, which are – VO2 Max and SpO2. Below, we have provided details on them to help you to differentiate between them. Hopefully, it will help you out in your future endeavor. 

What is the Difference between SpO2 and VO2 MAX?

So, the term, SpO2, refers to the idea of measurement of overall oxygen saturation in your blood. It is usually done by counting the total number of oxygenated hemoglobin, which runs through your arteries.

On the other hand, the VO2 measures the maximum amount of oxygen you can use while exercising. It is generally tested to assess the cardiovascular fitness or aerobic endurance of a person or athlete. 

Nevertheless, you should never mishmash them with your heart rate, as they are quite different than the latter.

Importance of Oxygen Level Monitoring or SpO2 

So, now, you are probably wondering why you should monitor your blood’s oxygen level? For starters, if your RBCs do not carry the proper amount of oxygen, it could mean that you are probably suffering from a cardiovascular ailment. Secondly, it can also help you to know if you are affected by anemia or not.

Moreover, if you do not have enough oxygen level in your blood, it may indicate the early signs of lung diseases! Due to these reasons, monitoring your oxygen becomes very crucial for everyone.

Nonetheless, doctors generally do not ask teenagers or young adults to check their SpO2. If you are a health-conscious person, we would ask you to monitor your oxygen level. Advanced smartwatches like Apple Watch Series 6, Samsung Galaxy Watch 3, and Fitbit Sense come with a blood oxygen level sensor along with an ECG sensor.

How do the Smartwatches Track Blood Oxygen? 

The smartwatches use a SpO2 sensor to measure blood oxygen level. When you wear it on your hand, it continuously emits lights into the skin and measures the oxygen level based on the amount of light absorbed by the blood.

You can check this in-depth guide on how SpO2 feature works on smartwatches. 


All the SpO2 smartwatches can give you in-depth data into your health and fitness. It also helps you optimize your performance based on various health measured by these devices. I hope this article on the best smartwatch with blood oxygen sensors helps you pick the right smartwatch to keep an eye on your SpO2, sleep, etc.

As a final note, if you are looking for a smartwatch with oxygen for Apple device, then Apple Watch Series 6 is the right smartwatch for you. If you are an Android phone user, you can go for Galaxy Watch 3 or Fitbit Sense. If you are runner or sports personnel, then go for a Garmin wearable.

Disclaimer: Even though most smartwatches mentioned here accurate measure oxygen, you should never use them for medical purposes. 

Saneesh VS is a Registered Nurse by Profession and Wearable Tech Enthusiast by Passion. He loves to write about fitness, smartwatches, and fitness trackers. He also loves reading books on wearable tech, technology in healthcare, artificial intelligence etc., which he has been writing for the past 5 years.

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