What is the Fitbit ECG app?

Atrial fibrillation (AFib) is a type of irregular heart rhythm, caused when the upper chambers of the heart beat out of rhythm. Normally, the heart's upper and lower chambers work together. With AFib, the upper chambers contract chaotically and quickly. As a result, the lower chambers contract faster than usual. This sequence can lead to an irregular heart rhythm.

Learn more from the CDC or by visiting the website of the European Society of Cardiology [https://escardio.org/].

The electrical sensors on your Fitbit wrist-worn product detect your heart rhythm. When you use the Fitbit ECG app, your heart rhythm data is analyzed for signs of AFib. Only a doctor can diagnose AFib, but the results of the assessment can let you know if your heart rhythm has signs of the condition.

With AFib, your heart may not always beat irregularly, making it hard to detect even in the doctor’s office. While this assessment can’t diagnose AFib, you can use it right from your wrist. Your results can help you have a better conversation with your doctor.

Certain Fitbit wrist-worn products have electrical sensors on the back of the product and on the metal frame around the face (Fitbit Charge 5, Fitbit Charge 6, Fitbit Sense, and Fitbit Sense 2) or crown (the dial on the outside of Google Pixel Watch, Google Pixel Watch 2, and Google Pixel Watch 3). When these sensors are in contact with your skin and the Fitbit ECG app is open, they record the electrical signals from your heartbeat. The Fitbit ECG app is qualitatively similar to a Lead I ECG in that it can be used to discriminate between AFib and normal sinus rhythm. However, it can’t detect all heart conditions. In a doctor’s office, a 12-lead ECG is typically used, which provides electrical information about the heart from 12 different angles.

You can find the Fitbit ECG app on your Fitbit wrist-worn product by swiping left on the screen (Charge 5, Charge 6, and Sense), by pressing the button (Sense 2), or by pressing the crown (Google Pixel Watch series). Past results can be found within the Health assessments section of the You tab in the Fitbit app on your phone or tablet.

If you don’t have the Fitbit ECG app installed, refer to How do I install the Fitbit ECG app?

Note that the Fitbit ECG app is only available in select locations at this time. If you’re not in a supported location, you'll get an error message that the feature isn't supported in your location.

Additional countries will be added as regulatory clearance is obtained.

Refer to Irregular Heart Rhythm for additional details.

If the Fitbit ECG app isn’t already installed on your Fitbit wrist-worn product, download it.

Before you take your first reading:

1. Open the Fitbit app on your phone or tablet, and log in to your Fitbit account if you haven’t already done so.
2. From the You tab in the Fitbit app, find the ECG tile in the Health assessments section. Tap Set up and follow the instructions. After you complete the Heart Rhythm Assessment introduction, you can take an ECG reading.

To take an ECG reading:

1. Wear your Fitbit wrist-worn product snugly, but with enough room for comfort. It should sit a finger’s width above your wrist bone. The back of the Fitbit wrist-worn product should rest securely against your skin. For more information, refer to How do I wear my Fitbit device?.
2. Sit down and open the ECG app on your Fitbit wrist-worn product. Note that after you tap the ECG app icon, it can take several seconds for the app to load. During this time, the product displays a black screen.
3. Follow the instructions on your Fitbit wrist-worn product to start the assessment.
4. Put your finger(s) on your Fitbit wrist-worn product as shown on the screen. Sit still while the test is in progress with your feet on the floor and forearms and wrists resting on a solid surface in front of you. Remain calm and relaxed, breathing regularly Continue to hold the contact point(s) until the countdown is complete. Avoid touching other parts of the Fitbit wrist-worn product or your wrist.
5. When your results appear, swipe up to check the full report. Note that Google Pixel Watch series must be connected to LTE or Wi-Fi to sync your ECG data to the Fitbit app.

After you complete the Heart Rhythm Assessment, you get one of the following results:

Normal sinus rhythm	Your heart rhythm appears normal. Tap Learn more for more information or tap Done to exit the assessment.
Atrial fibrillation	Your heart rhythm shows signs of AFib. You should contact your doctor. Tap Learn more for more information, or tap Done to exit the assessment.
Inconclusive	The Fitbit ECG app couldn’t get a good reading either because your heart rate was too low, too high, or there wasn’t a good enough signal. Tap Retake to try again, or tap Done to exit the assessment. For more information on why you might receive this result, refer to Why did I receive an inconclusive result?

There are 3 types of inconclusive results you might receive after taking the assessment:

Inconclusive: High heart rate

If your heart rate is over 120 bpm, the Fitbit ECG app can’t assess your heart rhythm. Heart rate can be high for many reasons, such as:

• Recent exercise
• Stress
• Nervousness
• Alcohol
• Dehydration
• Infection
• AFib, or other arrhythmia

Learn more from the American Heart Association or visit the website of the European Society of Cardiology [https://escardio.org/].

Inconclusive: Low heart rate

If your heart rate is under 50 bpm, the Fitbit ECG app can’t assess your heart rhythm. Heart rate can be low for many reasons, such as:

• Taking certain medications such as beta-blockers or calcium channel blockers
• Having excellent aerobic fitness
• Other arrhythmia

Learn more from the American Heart Association or visit the website of the European Society of Cardiology [https://escardio.org/].

Inconclusive: Didn't get a good reading

There are many possible reasons for getting an inconclusive result, but common causes are:

• Moving too much during the reading
• Not resting your hands on a table
• Wearing your device too loosely
• Uneven or strenuous breathing
• Wearing your device on a wrist other than the one you specified
• Being near electronics since this can interfere with the reading

If the Fitbit ECG app couldn’t get a good reading, try the following troubleshooting tips:

• Make sure you’re sitting down and relaxed.
• Rest your arms on a table while you take the assessment and avoid moving.
• Check that your Fitbit wrist-worn product is on the wrist you selected when you started the assessment. 
• Keep your finger(s) on your Fitbit wrist-worn product for the duration of the assessment. Avoid touching other parts of the Fitbit wrist-worn product or your other wrist.
• Check the fit of your Fitbit wrist-worn product. It should feel comfortably secure, not too loose or too tight. Wear it a finger’s width above your wrist bone. The back of the Fitbit wrist-worn product should rest securely against your skin. For more information, refer to How do I wear my Fitbit device?
• Ensure there is no interference with the electrode to skin contact (hair, jewelry, clothing, etc.)
• If you recently put on your Fitbit wrist-worn product, the electrodes might need to warm to your skin temperature. The electrodes are located on the side of the watch face for Fitbit wrist-worn products and on the bottom of the device for Google Pixel Watch series. Try retaking the assessment at a later time.
• Avoid taking the assessment after recent exercise because heavy breathing and elevated heart rate after exercise can make it challenging to obtain a good reading.
• Move away from other electronics to prevent interference.
• If you have dry skin, a small amount of lotion applied to your finger(s) and wrist can help the electrodes get a good reading.
• Make sure your Fitbit wrist-worn product and wrist are clean and dry. Water or sweat can interfere with the reading. If you recently washed your hands, went swimming, showered, or perspired, clean and dry your Fitbit wrist-worn product. Refer to Fitbit Product Care for wear and care instructions.

Retake the assessment to try again. If you get an inconclusive result repeatedly, or you’re not feeling well, talk to your healthcare provider.

If you remove your fingers from your Fitbit wrist-worn product or move too much during the ECG reading, the countdown timer restarts.

When you open the Fitbit app, your results transfer from your Fitbit wrist-worn product to the Fitbit app, and can be viewed on your phone or tablet. To check your results at a later time, such as during an appointment with your healthcare provider:

1. From the You tab in the Fitbit app, find the ECG tile in the Health assessments section. Tap View history to get a list of all your previous results. The results are displayed with the date and time that they were taken on the compatible Fitbit wrist-worn product. This reflects the time on the wrist-worn product and not the time of syncing your results. It also does not account for travel across time zones.
2. Tap any of the previous results to view the details. The results are displayed with the date and time that they were taken on the compatible Fitbit wrist-worn product.
   Note: If your Fitbit wrist-worn product wasn’t able to measure your heart rate, the ECG results might show dashes where your average heart rate normally appears. Follow the instructions in Inconclusive: Didn’t get a good reading to retake the assessment.
3. Within each result, tap Export a PDF for your doctor to download the report. You’ll receive a notification when your report is ready. We recommend using the latest version of Adobe Acrobat Reader to open the report.

1. From the You tab in the Fitbit app, find the ECG tile in the Health assessments section. Tap View history to get a list of all your previous results.
2. Tap the result you want to delete. Swipe to the bottom of the page, and tap Delete result.

The Fitbit ECG app was tested in a clinical study of 440 people. During the study, each person completed a 30-second 12-Lead ECG recording while simultaneously using the Fitbit ECG app. The Fitbit ECG app software algorithm was able to correctly identify people with AFib 98.7% of the time and correctly identify people with a normal sinus rhythm 100% of the time.

The Fitbit ECG app is currently available on Fitbit Sense (running Fitbit OS 5.0+), Fitbit Sense 2, Fitbit Charge 5, Fitbit Charge 6, Google Pixel Watch, Google Pixel Watch 2, and Google Pixel Watch 3.

To access the Heart Rhythm Assessment, install the Fitbit app on your phone or tablet. To verify that your phone or tablet is compatible with the Fitbit app, refer to Fitbit Compatible Devices.

Sync your Fitbit wrist-worn product to get your ECG results in the Fitbit app. If you have trouble syncing, refer to Why won't my Fitbit device sync? Note that Google Pixel Watch series must be connected to LTE or Wi-Fi to sync your ECG data to the Fitbit app.

The Fitbit ECG app uses electrical sensors on the back of your compatible Fitbit wrist-worn product and on the metal frame around its face (Fitbit Charge 5, Fitbit Charge 6, Fitbit Sense, and Fitbit Sense 2) or crown (Google Pixel Watch series) to allow you to record the electrical signals from your heartbeat during a 30-second reading. The Fitbit ECG app is qualitatively similar to a Lead I ECG in that it can be used to discriminate between AFib and normal sinus rhythm. The Fitbit ECG app analyzes the recording and presents the results on your watch or tracker.

Fitbit Irregular Rhythm Notifications collects pulse rate data in the background when you’re still or at rest by analyzing beat-to-beat measurements. It uses the optical pulse-rate sensor on your compatible wrist-worn product to identify heart rhythm changes. If multiple readings show an irregular pulse rate that may be AFib, you receive a notification. Data isn’t analyzed in real-time. For more information, refer to How do Fitbit Irregular Rhythm Notifications check for atrial fibrillation (AFib)?