Over the summer, Apple made a huge splash when it announced the Apple Watch Series 4 would be the first over-the-counter device to offer ECG readings. With this week’s update to watchOS 5.1.2., the feature is finally available for Series 4 owners to try. Here’s how to use it.

According to Apple, the new feature is capable of detecting signs of atrial fibrillation, a serious form of irregular heart rhythm. The feature is only available to Apple Watch users in the US.


  1. Update your Watch and iPhone to the latest software
  2. Head into the iPhone’s Health app and set up ECG by following the prompts


  1. Tap the ECG app
  2. Ensure your Apple Watch is snug on your wrist
  3. Place your finger on the watch’s Digital Crown for 30 seconds
  4. Once the countdown is done, lift your finger off the Digital Crown

Once that process is complete, the Health app will display your results. If you have a sinus rhythm, it means your heart is beating in a uniform pattern. An AFib result means your heart is beating in an irregular pattern.

Apple says that the ECG app cannot detect a heart attack, blood clots, stroke, or other heart-related conditions. If you do get a result that’s concerning, talk with your doctor.