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

Days are gone when you had to goes to a hospital to check your vital signs. Today, smartwatches comes with advanced health tracking features such asheart rate monitoring, irregualar heart rate alerts, blood oxygen level, ECG, irregular heart rhythm detection, etc.

Today I have compiled a list of the best smartwatch with a blood oxygen sensor that tracks your SpO2 right from your smartwatch. If you are looking for a smartwatch with ECG, you can check my previous article on the best FDA Approved ECG Smartwatches in 2021.  

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

Additionally, there is a massive demand for smartwatches with oxygen sensors in today’s world because of current COVID Pandemic. COVID- 19 pandemic. A group of researchers assessed the smartwatch data of COVID-19 patients and found a visible variation in their heart rate, blood oxygen level, and temperature even days and weeks before they were diagnosed with COVID-19. You can find a detailed study here.

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

There are two types of SpO2 smartwatches available in the market today. 

Types of Smartwatches with SpO2

Smartwatches with Real-time SpO2: These types of smartwatches allow you to take SpO2 reading anywhere at any time. Most of the blood oxygen monitoring smartwatches with real-time oxygen come with a SpO2 app to record oxygen level. Most of the smartwatches essentially take 30 seconds to measure the SpO2. These smartwatches help you take an oxygen reading immediately if you are not feeling well.  

Samsung Galaxy Watch 3, Active 2, Apple watch Series 6, etc. are great examples of smartwatches with real-time blood oxygen. 

Smartwatches with nighty SpO2: These type of 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 oxygen, and it is a limitation. This makes these smartwatches less preferable for people who want to take frequent SpO2 readings. 

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 out on mobile payment apps 

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 can not go more than 18 hours like its predecessors. Here is an in-depth article on how to save battery life on Apple watches. Trying these tips may help you extend the battery life of your Apple watch a few more hours.


  • 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 a 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

The Garmin Forerunner 945 also comes with a wrist-based oxygen sensor. As it name suggests, it is made by keeping runners in mind, and it tracks all activities along with important body metrics. 

As it gives you essential metrics on your wrist, you can adjust your performance based on heat, heart rate, SpO2, recovery time and training effects. 

It also featured an advanced GPS sensor for navigation. As a result, you can have detailed data into your pace; distance travelled, etc.


  • 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 
  • Buy Now From Amazon

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 haemoglobin, 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. 

Another difference between these two is that SpO2 is generally measured in percentage. However, the VO2 Max is usually assessed in millimetres. Otherwise, the purpose of these two is the same. Each of them can help you to understand about your heart’s condition.

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 anaemia 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 a 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 Registred Nurse By Profession and Wearable Tech Enthusiast by Passion.

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