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Yes. The U.S. Food and Drug Administration cleared Google’s opt-in Loss of Pulse Detection feature for Pixel Watch 3 on February 26, 2025. The feature looks for a potential loss of pulse while the watch is being worn and, if the wearer does not respond to alerts, attempts to contact emergency services. Clearance is not a guarantee that every event will be detected or that an emergency call will connect.
What does Loss of Pulse Detection do?
Loss of Pulse Detection monitors for a possible absence of pulse. If its checks indicate a potential event, the watch first asks the wearer to respond. If the wearer does not, the watch attempts to call emergency services and provide location information.
Google Product Manager Edward Shi announced the U.S. FDA clearance on February 26, 2025, writing: “Loss of Pulse Detection has received U.S. FDA clearance, and is now available on Pixel Watch 3.” The feature first launched in European markets and rolled out in the United States at the end of March 2025.
FDA clearance is regulatory authorization for this particular feature; it does not mean the watch is a general-purpose heart monitor or that it can reliably detect every emergency. Google says the feature cannot diagnose, treat or determine the cause of a loss of pulse.
#1 Best Overall
- The Google Pixel Watch 3 is designed for performance, with advanced fitness from Fitbit[1,2]; the 45mm screen is twice as bright and 40% larger than before, making it easier to see your stats and info[1]
- Maximize your performance with advanced running features; build custom run workouts and get real-time guidance and advanced form tracking[3]
- Enhance your run routine with Fitbit Premium; Google AI uses your goals, past runs, and readiness to power personalized run recommendations[3]
- Know what your body is ready for each day with readiness; it uses sleep, resting heart rate, and heart rate variability to show if you’re ready to take on a workout or prioritize recovery[3]
- Cardio load measures how hard your heart works so you can see how hard you’ve pushed; compare trends to see if you’re under- or over-training[3]
How does Pixel Watch 3 check for a loss of pulse?
Sensor checks before an alert
The process begins with the watch’s optical heart-rate sensor. If its pulse signal disappears, the watch uses infrared and red lights to make additional checks while its motion sensor looks for movement. Google says the system also checks that the watch is being worn, looks for motion and increases the optical signal before showing an alert. These passive checks can take up to 20 seconds and are intended to reduce false alerts.
An AI-based algorithm combines pulse and movement signals before the watch escalates. Google describes the system as using “signals from Pixel Watch 3’s sensors, AI and signal-processing algorithms.” Poor sensor readings, motion artifacts, ambient light, pressure on the skin and individual differences can still lead to a check-in when no emergency is occurring.
Google’s reported development work
Google’s engineering article, published August 13, 2024 and updated February 26, 2025, says development included cardiologist input, data collected in clinical settings and hundreds of thousands of hours of real-life user data from a diverse group of people. Google also says stunt actors wore tourniquets to simulate pulselessness and falls while the team validated emergency scenarios. Those are Google’s descriptions of its development process, not independent confirmation of performance.
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Rank #2
- The Google Pixel Watch 3 is designed for performance, with advanced fitness from Fitbit[1,2]; the 41mm screen is twice as bright and 10% larger than before, making it easier to see your stats and info[1]
- Maximize your performance with advanced running features; build custom run workouts and get real-time guidance and advanced form tracking[3]
- Enhance your run routine with Fitbit Premium; Google AI uses your goals, past runs, and readiness to power personalized run recommendations[3]
- Know what your body is ready for each day with readiness; it uses sleep, resting heart rate, and heart rate variability to show if you’re ready to take on a workout or prioritize recovery[3]
- Cardio load measures how hard your heart works so you can see how hard you’ve pushed; compare trends to see if you’re under- or over-training[3]; and receive a daily target based on cardio load and readiness levels
What happens if the watch detects a possible event?
- Check-in: The watch vibrates and displays a prompt asking the wearer to respond. Google Help says this prompt remains for about 15 seconds.
- Alarm and countdown: If there is no response, an audible alarm sounds and an approximately 20-second countdown begins.
- Attempted emergency call: When the countdown ends, a connected phone or an LTE watch attempts to call emergency services and provide location information.
The feature does not guarantee a call will connect. A depleted battery, inadequate mobile service, a disconnected phone or other network conditions can prevent the call or affect location sharing.
How well did the feature perform in the published figures?
Google/Fitbit’s Instructions for Use, Revision C, reports 69.3% sensitivity across 135 users. In the same document, specificity was analyzed using 131 evaluable participants and resulted in one false-positive call over 7.75 user-years. These figures describe the document’s study context; they should not be read as a guarantee for an individual user or as a measure of performance in every real-world emergency.
Where is Loss of Pulse Detection available?
Google’s current Pixel Watch Help page lists support in Austria, Belgium, Canada, Denmark, France, Germany, Ireland, Italy, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom and the United States. Availability can depend on region and connectivity. If the wearer travels into a region where the feature is unsupported, detection and calling are temporarily suspended.
Rank #3
- The Google Pixel Watch 3 is designed for performance, with advanced fitness from Fitbit[1,2]; the 45mm screen is twice as bright and 40% larger than before, making it easier to see your stats and info[1]
- Maximize your performance with advanced running features; build custom run workouts and get real-time guidance and advanced form tracking[3]
- Enhance your run routine with Fitbit Premium; Google AI uses your goals, past runs, and readiness to power personalized run recommendations[3]
- Know what your body is ready for each day with readiness; it uses sleep, resting heart rate, and heart rate variability to show if you’re ready to take on a workout or prioritize recovery[3]
- Cardio load measures how hard your heart works so you can see how hard you’ve pushed; compare trends to see if you’re under- or over-training[3]
What does the feature need to place an emergency call?
- Wi-Fi Pixel Watch 3: The watch needs a Bluetooth-connected phone to attempt an emergency call.
- LTE Pixel Watch 3: The watch needs an active LTE connection; some regions also require an active carrier or Safety Signal.
- Either model: The watch and any required phone must be charged and have adequate connectivity. Network availability and conditions still determine whether a call can connect.
Who should not rely on Loss of Pulse Detection?
Google says the feature is not intended for people under 22, people whom clinicians have identified as being at high risk for sudden cardiac death, or people prescribed continuous cardiac or pulse monitoring. It does not replace medical monitoring, and people with those needs should follow their clinician’s guidance rather than rely on the watch.
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- On the paired phone, open the Google Pixel Watch app.
- Tap Safety & emergency, then choose Loss of Pulse Detection.
- Complete the onboarding steps. You must be signed in to Personal Safety with a Google Account.
Detection operates only while the watch is being worn. If the Loss of Pulse Detection option is missing in a supported region, Google advises updating the Personal Safety app on the watch and the Pixel Watch app on the phone.
What happens to the data?
Google says feature data, including heart-rate and movement data when a loss is detected, is stored on Google servers and is not sold or used for advertising.
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