Apple Watch can be used to determine your blood oxygen levels throughout the day. This is made possible by the use of red and near-infrared (IR) LED lights that detect light photo signals from your perfused tissues and translate them into SpO2 values using conventional pulse oximetry methods. This value, displayed as a percentage, tells you how much oxygen your red blood cells are carrying from your lungs to the rest of your body.
How do you measure your blood oxygen level with an Apple Watch?
In this post, we'll explain what you need to measure your blood oxygen level on your Apple Watch, and how to take and view these measurements on your wrist or on your iPhone.
Blood oxygen measurement is not available on all Apple Watch models available. To perform a blood oxygen measurement, Apple Watch requires an optical system consisting of green, red, and infrared LEDs and photodiode sensors that can measure the oxygen saturation of arterial hemoglobin in your body. This system is only available on the following Apple Watch models:
If you own an Apple Watch Series 5 or older model, or a Watch SE model, you cannot measure your blood oxygen level with your device.
