How Accurate is Fitbit Heart Rate Tracking? Is it Accurate? Read on to learn the complete truth!
Fitbit has gained immense popularity as a wearable fitness tracker, offering users the ability to monitor their heart rate as a key health indicator. But how accurate is Fitbit’s heart rate tracking? In this article, we dive straight into the facts to uncover the truth behind Fitbit’s pulse precision.
We will explore the technology behind Fitbit’s heart rate monitoring, evaluate its accuracy against scientific benchmarks, and examine potential limitations. By the end, you’ll have a candid understanding of Fitbit’s reliability when it comes to tracking your heart rate. Let’s get started!
- How does Fitbit Track Heart Rate?
- How Accurate is Fitbit Heart Rate Tracking?
- Which Fitbits have Heart Rate Tracking, ECG, and AFib Detection?
- What are the Potential limitations of Fitbit’s heart rate tracking?
- Tips for getting the most accurate heart rate readings from your Fitbit
- How does the Fitbit ECG app work?
- FAQS
- Conclusion
How does Fitbit Track Heart Rate?
Fitbit utilizes optical heart rate monitoring technology to track heart rate. The device uses LEDs and photodiodes to measure blood volume changes under the skin. When the LEDs emit light onto the skin, the photodiodes detect the reflected light, which varies based on the volume of blood flowing through the capillaries.
Fitbit devices typically use green light, as it is easily absorbed by blood and provides accurate readings. Some models may also employ additional colors, such as red or infrared, to enhance accuracy in different scenarios. The reflected light data is then processed through algorithms to calculate heart rate based on the detected blood volume changes.
Fitbit devices employ continuous heart rate monitoring, capturing heart rate data at regular intervals throughout the day, including during rest, exercise, and sleep. This data is then displayed on the device’s screen or synchronized with a companion app, allowing users to track their heart rate trends and monitor their cardiovascular health and fitness levels over time.
It is important to note that Fitbit heart rate tracking is designed for general fitness and informational purposes and is not intended to replace professional medical devices or assessments.

If you want to learn How does Fitbit Track Steps, check out this guide.
How Accurate is Fitbit Heart Rate Tracking?
The accuracy of Fitbit’s heart rate tracking has been studied in a number of clinical trials. In general, Fitbit’s heart rate tracking is more accurate at rest and during low-intensity activities than during high-intensity activities.
One study, published in the journal Medicine & Science in Sports & Exercise, found that Fitbit’s Charge HR and Surge trackers were accurate within 5 beats per minute of an ECG at rest. However, the accuracy of the trackers decreased to 10 beats per minute during moderate-intensity exercise and 20 beats per minute during vigorous-intensity exercise.
Another study, published in the journal Heart, found that Fitbit’s Charge 2 tracker was accurate within 8 beats per minute of an ECG at rest and during low-intensity activities. However, the accuracy of the tracker decreased to 15 beats per minute during moderate-intensity exercise and 25 beats per minute during vigorous-intensity exercise.
Independent studies and user experiences have shown that Fitbit heart rate tracking can be fairly accurate during moderate-intensity activities. In most cases, Fitbit Heart Rate Tracking can be accurate up to 95% but there are always exceptions. However, accuracy may vary depending on factors such as individual physiology, device placement, and environmental conditions.
Fitbit’s heart rate tracking tends to perform better during steady-state exercises like walking, jogging, or cycling. The accuracy may decrease during high-intensity exercises or activities involving rapid movements, as the device may struggle to maintain consistent contact with the skin and accurately capture rapid changes in heart rate.
Factors such as sweat, tattooed skin, improper device fit, and excessive motion can potentially affect the accuracy of Fitbit heart rate readings. Device placement on the wrist, particularly the tightness of the strap, is crucial for obtaining reliable measurements.
Fitbit acknowledges these limitations and advises users to use heart rate data as a general guideline rather than relying on it as a precise medical measurement. It is always recommended to consult with healthcare professionals for a comprehensive and accurate assessment of cardiovascular health.
In summary, while Fitbit’s heart rate tracking can provide useful insights for most individuals during moderate activities, it may not be as accurate during high-intensity exercises or for specific individuals. It’s important to consider these factors and use Fitbit heart rate data as a supportive tool rather than a definitive medical measurement.
What are the Potential limitations of Fitbit’s heart rate tracking?
Fitbit’s heart rate tracking, like any technology, has its limitations. Here are some potential factors that may impact the accuracy of Fitbit’s heart rate measurements:
- Device Fit and Placement: Fitbit devices must be worn snugly on the wrist for optimal accuracy. If the device is too loose or moves around during activities, it may lead to inaccurate readings.
- Individual Variations: Factors such as skin tone, tattoos, and skin conditions can affect how well the device’s sensors interact with the skin and impact the accuracy of heart rate tracking.
- Intense Physical Activities: During high-intensity exercises or activities involving rapid movements, Fitbit’s heart rate tracking may struggle to capture quick changes in heart rate accurately. Intermittent contact with the skin due to excessive motion can affect the reliability of readings.
- Environmental Conditions: Environmental factors such as extreme temperatures, humidity, or altitude can potentially impact the accuracy of heart rate tracking.
- Optical Interference: Certain lighting conditions, such as intense sunlight or artificial light sources, may interfere with the accuracy of the optical sensors used by Fitbit devices, leading to less reliable heart rate measurements.
- Device-Skin Interaction: Sweat, moisture, or dirt on the skin or device sensors can affect the quality of the contact and compromise the accuracy of heart rate tracking.
Tips for getting the most accurate heart rate readings from your Fitbit
Here are some tips for getting the most accurate heart rate readings from your Fitbit:
- Wear the device snugly but comfortably. The device should be snug enough to stay in place, but not so tight that it is uncomfortable.
- Make sure the device is clean and dry. Sweat and dirt can interfere with the device’s ability to track your heart rate.
- Avoid wearing the device over a tattoo. Tattoos can interfere with the device’s ability to track your heart rate.
- Don’t move your arm too much. Moving your arm too much can interfere with the device’s ability to track your heart rate.
- Check the device’s battery level. A low battery can affect the accuracy of the device’s heart rate tracking.
How does the Fitbit ECG app work?
Fitbit’s ECG app uses two electrical sensors on the back of the device and on the metal frame around the face to record the electrical signals from your heartbeat during a 30-second reading. The ECG app analyzes the recording and presents the results on your watch or tracker.
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 is not intended for diagnostic purposes. The app is a spot check that analyzes the recording and presents the results. The ECG data can be used for non-clinical applications, such as providing an estimate of your heart rate.
To use the Fitbit ECG app, you must first set it up in the Fitbit app on your phone or tablet. Once the app is set up, you can open it on your watch or tracker and follow the instructions. The app will guide you through the process of placing your fingers on the electrical sensors and recording your ECG.

Which Fitbits have Heart Rate Tracking, ECG, and AFib Detection?
Here are current Fitbit models and their heart rate tracking, ECG, and AFib detection capabilities
Model | Heart Rate Tracking | ECG | AFib Detection |
---|---|---|---|
Fitbit Charge 5 | Yes | Yes | Yes |
Fitbit Sense | Yes | Yes | Yes |
Fitbit Sense 2 | Yes | Yes | Yes |
Fitbit Versa 3 | Yes | No | No |
Fitbit Versa 4 | Yes | No | No |
Fitbit Inspire 2 | Yes | No | No |
Fitbit Inspire 3 | Yes | No | No |
Fitbit Luxe | Yes | No | No |
Fitbit Ace 3 | Yes | No | No |
Fitbit Flex 2 | Yes | No | No |
Fitbit Charge 4 | Yes | No | No |
Fitbit Charge 3 | Yes | No | No |
Fitbit Alta HR | Yes | No | No |
Fitbit Charge HR 2 | Yes | No | No |
Fitbit Surge | Yes | No | No |
Fitbit Blaze | Yes | No | No |
Fitbit Ionic | Yes | No | No |
Fitbit Versa | Yes | No | No |
Fitbit Versa Lite | Yes | No | No |
FAQS
Which Fitbit Smartwatches have ECG?
The Fitbit ECG app is available on the following devices:
1. Fitbit Charge 5
2. Fitbit Sense
3. Fitbit Sense 2
4. Google Pixel Watch
Which Fitbits have Heart Rate Tracking in 2023?
Here are the Fitbits that have heart rate tracking in 2023:
1. Fitbit Charge 5
2. Fitbit Sense
3. Fitbit Sense 2
4. Fitbit Versa 3
5. Fitbit Versa 4
6. Fitbit Inspire 2
7. Fitbit Inspire 3
7. Fitbit Luxe
8. Fitbit Ace 3
9. Fitbit Flex 2
10. Fitbit Charge 4
11. Fitbit Charge 3
12. Fitbit Alta HR
13. Fitbit Charge HR 2
14. Fitbit Surge
15. Fitbit Blaze
16. Fitbit Ionic
17. Fitbit Versa
18. Fitbit Versa Lite
Which Fitbits have AFib detection?
In 2023, Following Fitbits have AFib detection
1. Fitbit Charge 5
2. Fitbit Sense
3. Fitbit Sense 2
4. Google Pixel Watch
Conclusion
Fitbit’s heart rate tracking is a valuable tool for tracking your fitness and health. However, it is important to be aware of its limitations. By following the tips in this article, you can get the most accurate heart rate readings from your Fitbit. If you are still concerned about the accuracy of your heart rate readings, you should consult with a doctor.