Why does it take a few seconds for my Apple Watch to show my heart rate?

If your Apple Watch takes more than 10 seconds to display your current heart rate, it could be due to a physical issue with the sensor or how the watch is worn.

🧼 Try cleaning the sensor

The green light on the back of your Apple Watch is part of the optical heart rate sensor. Dirt, oil, or sweat can interfere with its accuracy and responsiveness.

To improve heart rate detection:

• Gently clean the back of your Apple Watch with a soft, dry cloth

• Make sure the watch is snug but comfortable on your wrist

• Avoid wearing it too loosely during workouts or while measuring heart rate

🔁 Restart your devices

If the problem continues after cleaning:

Restart your Apple Watch
Restart your iPhone
Open Cardiogram again and check your heart rate display

✅ Best Practices for Accurate Heart Rate Readings on Apple Watch

If your Apple Watch is slow to show your heart rate or if the readings seem off, follow these tips to get the most accurate results:

📍 Watch Placement

Wear your watch snug, not tight — it should stay in place but still be comfortable
Make sure it sits above the wrist bone, not directly on it
Adjust the band for a closer fit during workouts

🧼 Sensor Maintenance

Clean the back of your Apple Watch regularly with a soft, lint-free cloth
Remove sweat, oil, or dirt buildup from the sensor area
Keep both the sensor and your skin dry for best results

⚙️ Settings & Behavior

Make sure heart rate tracking is enabled in iPhone > Settings > Privacy & Security > Health > Heart Rate
Use Workout mode in the Workout app or Cardiogram for continuous readings
Avoid wrist movements that may loosen the watch or cause misalignment

🔁 Troubleshooting

If your heart rate doesn’t show after 10+ seconds:
- Restart both your Apple Watch and iPhone
- Check Health app permissions to ensure Cardiogram has access to your data

Still having trouble?

Email us at [email protected] and we’ll help you troubleshoot.