How to Use the Apple Watch Oximeter

How to Use the Apple Watch Oximeter

The oximeter is a feature present in models from the Apple Watch 6 that allows you to monitor the oxygen level directly from the wrist. In this way, it is possible to have a previous diagnosis of health and to know if there is a need for emergency medical assistance.

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Smart watch sensors are responsible for measuring the amount of reflected light and the color of the blood: bright red blood indicates good oxygen level, and dark red indicates low level. Healthy people have between 95% and 100% oxygenation in their blood.

How to measure blood oxygen by Apple Watch

Before starting your oximeter measurement routine, make sure your devices meet the necessary requirements and follow the method below to properly configure the feature on your Apple Watch and iPhone.


  • Have an Apple Watch 6 and iPhone 6s or higher.
  • iPhone must be updated to the latest version of iOS.
  • Apple Watch must be paired with iPhone and updated to the latest version of watchOS.
  • Be over 18 years old and confirm your age in the Health app.

Feature Setup on iPhone

  • Open the Watch app;
  • Tap “Blood Oxygen”;
  • Activate the “Blood Oxygen Measurements” option;
  • Measurement with Apple Watch

    Make sure your Apple Watch is snug and comfortable on your wrist — remember your arm should be still and relaxed for the most accurate results. Follow the steps below:

  • Open the Blood Oxygen app;
  • Tap “Start”;
  • Wait for the measurement of oxygen in your blood to be completed;
  • After the result appears, tap “OK”.
  • measurement history

    By default, Apple Watch constantly takes measurements in the background to take advantage of downtime and continuously check your blood oxygen level. To access your history, follow the steps below:

  • On iPhone, open the Health app;
  • Tap “Explore”;
  • Enter “Respiratory”;
  • Select the “Blood Oxygen” option.
  • Pause background measurement

    In dark environments, it is possible that the bright light from the oxygen measurement sensor may bother you. Also, constantly using the feature in the background consumes more of your Apple Watch’s battery. So you can set the watch not to measure blood oxygen on certain occasions.

  • On iPhone, open the Watch app;
  • Tap “Blood Oxygen”;
  • Under “Allow background measurements”, choose whether to keep them in Sleep Mode and Theater Mode.
  • Remember not to use the device as a medical reference. The information contained in the app reveals your fitness and well-being. If any specific symptoms appear, consult a health professional to receive the appropriate treatment.