How to use ECG on Fitbit Charge 5

A step-by-step guide on how to make the most of Fitbit's heart health tracking feature
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When the Fitbit Charge 5 was introduced with an ECG sensor, it became the first fitness band to pack in sensor technology capable of delivering the kind of heart rate monitoring accuracy that could help detect signs of serious heart health conditions.

Joining the likes of the Apple Watch, Samsung Galaxy Watch 4, Withings ScanWatch and Fitbit's own Sense, it also meant you didn't have to own a full-fat smartwatch or spend huge amounts of money to access what could be for many, a very desirable feature.

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If you've got a Fitbit Charge 5 and you're currently getting to grips with how it works and want to know why and how to use the ECG feature, we've broken down the key things you need to know about it, plus, take you through what to do to take that first ECG reading.

What is ECG and why is it important?

We've gone into more detail about this subject in our ECG and wearables guide, but to keep things simple, ECG (or EKG) stands for electrocardiogram. Unlike optical heart rate sensors, which use light to generate heart readings, ECG detects the timing and strength of the electrical activity in your heart. It has long been considered the most reliable method to monitor heart rate activity.

It's an important feature to have if you have general concerns about your heart health. Like the other devices mentioned above, the Charge 5 uses the ECG primarily to offer users the ability to more accurately track heart rate activity and it can also be used to identify potential signs of the medical condition atrial fibrillation.

Atrial fibrillation, which is also known as arrhythmia and sometimes shortened to Afib, refers to having an irregular heartbeat or a quivering heartbeat. This condition could lead to a stroke or heart failure.

So while it might not be a feature that everyone will feel they need to have in their lives, it could be a valuable way for many who do want to keep a much closer and more accurate eye on their heart.

How does ECG work on the Fitbit Charge 5?

To deliver those ECG measurements, Fitbit places sensors inside of the metal case and the biosensor core built into the Charge 5. When you're ready to take a measurement, you'll need to place your fingers on the sides of the Charge 5's metal case to start reading those electrical signals from your heart through your fingers.

Readings are then sent to the Fitbit app (iOS and Android) where you can review data and also have the ability to download and share results with a doctor or medical professional.

What you need to do first

These are some obvious things to do first, but make sure your device and the companion Fitbit app you use to pair and sync your Charge 5 tracker to your phone is up to date. We have a step-by-step guide on how to update your Fitbit if you're still unsure how to do this.

One of the simplest ways to check everything is up to date is to go to the app store where you downloaded the Fitbit app from and search for the Fitbit app. If you're not offered the option to update it, you should be all good.

You can also go to the Account section on the Fitbit phone app and select your paired Charge 5 to make sure it's running the latest firmware version.

How set up ECG on the Charge 5

How to use ECG on Fitbit Charge 5

Once the companion Fitbit phone app and the Charge 5 is up to date, here's the steps you need to go through to set up the ECG feature:

  • Tap the Charge 5 to wake it and then swipe right until you see the ECG screen
  • When you tap to take a reading it will prompt you to go to the Discover section on the Fitbit app. Look for the Assessments & Reports icon and select Heart Rhythm Assessment.

How to use ECG on Fitbit Charge 5

From here, the Fitbit app explains how the assessments work, what atrial fibrillation actually is along with possible symptoms. it also explains who this is assessment is best designed for. Fitbit makes it clear that this it's not designed for anyone under 22 years of age or has a pacemaker.

Once you understand that this is an assessment and not a diagnosis, Fitbit outlines its privacy policy with the electrical sensor data it collects, which can be used in research to improve existing devices and help develop future ones.

Fitbit will also explain the types of results you might see (which we'll cover later), and then you're ready to take your first ECG reading.

How to take an ECG reading on the Fitbit Charge 5

How to use ECG on Fitbit Charge 5

  • First, make sure your Charge 5 is worn snugly and is sat a finger-width above your wrist bone
  • Next, sit down somewhere and make sure you're in a relaxed state
  • Open the ECG app on the Charge 5 and select which wrist you're wearing the device on
  • When prompted, place your fingers on the side of the case and do it until the 30-second countdown on the screen is completed.
  • If the reading was a success, you'll be notified on the device's screen and it will generate the results.

What the results mean

How to use ECG on Fitbit Charge 5

There are three types of results you can expect to see after you've taken an ECG reading:

Normal sinus rhythm - This means your heart rhythm is considered normal and doesn't show signs of Afib.

Atrial fibrillation (Afib) - Your reading shows signs of Afib, which means you should contact your doctor.

Inconclusive - If you heart rate is over 120bpm or under 50bpm, the sensor will not be able to assess your heart rhythm. This inconclusive result can be caused by moving around too much when a measurement is being taken.

How to view and share ECG data

How to use ECG on Fitbit Charge 5

If you want to review heart rhythm assessment results, go to the Discover tab on the Fitbit companion phone app and select Heart Rhythm Assessment and you'll find a Results section. It will provide results along with the date and the time of the assessment.

If you want to share your results, each assessment offers the option to export a PDF for your doctor at the bottom of the screen. Tap that button to generate the PDF and it will be created and saved in the downloads section on your phone.

How we test

Michael Sawh


Michael Sawh has been covering the wearable tech industry since the very first Fitbit landed back in 2011. Previously the resident wearable tech expert at Trusted Reviews, he also marshaled the features section of

He also regularly contributed to T3 magazine when they needed someone to talk about fitness trackers, running watches, headphones, tablets, and phones.

Michael writes for GQ, Wired, Coach Mag, Metro, MSN, BBC Focus, Stuff, TechRadar and has made several appearances on the BBC Travel Show to talk all things tech. 

Michael is a lover of all things sports and fitness-tech related, clocking up over 15 marathons and has put in serious hours in the pool all in the name of testing every fitness wearable going. Expect to see him with a minimum of two wearables at any given time.

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