Check blood oxygen with Apple Watch: How-to

Whether it’s been a while since you’ve used the feature or never have – follow along for how to check blood oxygen with Apple Watch. We’ll also cover which models support the feature and how reliable the measurements are, and more.

Supported models and reliability

Apple Watch gained the ability to measure blood oxygen with Series 6 and has been included with each Apple Watch model since. That is until a legal battle with Masimo forced Apple to remove the feature starting January 18, 2024 from the latest Apple Watch models.

Fortunately, anyone with an Apple Watch 6-9 or Ultra/2 purchased before January 18 or, more specifically, a model number without “LW/A” at the end will not lose the blood oxygen capability. Read more on that in our full explainer:

As for efficacy, in multiple studies, the Apple Watch blood oxygen feature has proved as reliable as “medical-grade” devices.

How to check blood oxygen with Apple Watch

1. On your Apple Watch – purchased before January 18, 2024 – look for the red and blue rotating circle icon or ask Siri to launch “Blood Oxygen”
   • Note: Apple Watch Series 9 and Ultra 2 with the feature disabled will still show the app but it won’t work
2. Make sure your watch is snug and not too low on your wrist
3. Tap the Start button
4. Keep your watch as still possible and facing up during the measurement

Here’s how a successful blood oxygen with Apple Watch reading looks:

Tips to get a successful blood oxygen reading

If you’re seeing an “unsuccessful measurement” error, Apple says to:

• “Make sure your watch is not to low on your wrist.”
• “Your watch band should be snug, but comfortable.”
• “Keep your watch facing up and try not to move.”
• “Resting your wrist on a table can help.”

Check blood oxygen data on iPhone

• On iPhone, open the Health app
• Tap Browse in the bottom right corner
• Swipe down and choose Respiratory
• Blood Oxygen should be at the top

Thanks for reading our guide on how to check blood oxygen with Apple Watch!

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