How to Measure Your Heart Rate and Blood Oxygen (SpO2) Using iPhone

BY Sanuj Bhatia

Published 25 May 2021

blood oxygen spo2 monitoring on iPhone

Given the ongoing pandemic, having access to a pulse oximeter can be handy as it can be used to measure one’s blood oxygen levels instantly. However, you might find yourself in a situation where you do not have access to a pulse oximeter. In such scenarios, you can use your iPhone to measure your blood oxygen (SpO2) levels.

COVID-19, unfortunately, is still affecting the lives of millions of people around the world. With the medical system in many countries under extreme load, it is possible that you might not be able to purchase a pulse oximeter for an emergency due to demand-supply imbalance.

With blood oxygen levels being an important indicator of COVID turning ugly, oximeters have saved millions of lives worldwide. Thankfully, there’s a way for you to measure your blood oxygen levels easily using your iPhone, all without any external accessory.

Measuring SpO2 Levels Using your iPhone: Things to Know

  • CarePlix Vitals is an app developed by an Indian startup CareNow Healthcare (India), in collaboration with Careplix Healthcare (US).
  • The app lets you measure ‘vitals’ like blood oxygen levels, heart rate, and even respiration rate using only your iPhone. It doesn’t even require any external peripheral to work.
  • The user needs to place the index finger on the rear camera while covering the camera and flashlight completely.
  • The app takes the scans the light pulses through the camera for about 30 seconds and then shows the blood oxygen levels.
  • Do note that this app is not an alternative to a real pulse oximeter. Its results might not always be 100 percent accurate.

How to Measure Blood Oxygen Level and Heart Rate Using iPhone

Follow these step-by-step instructions to measure blood oxygen level and heart rate using your iPhone:

Step 1: Open the CarePlix Vital app on your iPhone and sign up for the free service.

Download – CarePlix Vitals (Free)

Step 2: On the main page, tap on Scan Vitals.

Step 3: A calibration window will pop up. Place your index finger on the camera in a way that your finger covers both the camera sensor and the flash.

It’ll show the signal strength underneath the small camera window. Make sure you’re covering the whole part for accurate results.

careplix vitals scan results blood oxygen iphone

Step 4: Wait for the scan to start. Once the scan starts, it’ll show the real-time blood oxygen level, heart rate, and respiration rate. Do not remove your finger in between the process.

Step 5: Once the scan is complete, a window with your measurements will pop up. You can save the result on this screen or start a new scan.

You can also check out our step-by-step video tutorial to learn how to measure blood oxygen (SpO2) and heart rate using your iPhone:

Subscribe to the iPhoneHacks YouTube channel for more videos.

During my testing, the app seemed to be very accurate. With the app, my SpO2 levels and heart rate came out to be 98 and 81, respectively. Using a proper oximeter, my SpO2 and heart rate came out to be 98 and 80, respectively. That’s an error of less than 2%.

Of course, the results may vary from person to person and condition to condition, but it’s still a handy way of measuring your oxygen levels. Given the situation right now, this app might prove useful for millions of people around the world.

After some amount of scans (the exact number isn’t mentioned), the app can also provide you ‘vital analytics’ based on the result history. This might prove useful for detecting high heart rates and other diseases. CareNow says that heart rhythm and PPG (an ECG equivalent) are in the works and will be available on the app soon.

If you’re looking for a device that can measure blood oxygen levels on the go, you might want to consider buying Apple Watch Series 6. Or you can even wait for Apple Watch Series 7 that is expected to feature real-time blood glucose monitoring.


Were you able to get your blood oxygen levels using the app? How accurate were the results? What was your experience with the app? Let us know in the comments section below!