Defective Products

Fitbit Heart Rate Monitors Fraud & Defects Lawsuit

Allegation: Fraud and misrepresentation

On January 5, 2016, Lieff Cabraser and co-counsel filed a fraud class action lawsuit on behalf of consumers nationwide against Fitbit, Inc. over complaints that heart rate monitors sold by Fitbit — the Fitbit Blaze, Charge HR and the Fitbit Surge — fail to accurately measure user heart rates. Complete the form below to learn more about your legal rights and help us hold Fitbit accountable.

On May 19, 2016, plaintiffs filed an amended complaint citing, among other things, a comprehensive new study conducted by researchers at California State Polytechnic University, Pomona revealed that the PurePulse™ heart rate monitors in the Fitbit Surge™ and Charge HR™ bear an “extremely weak correlation” with actual users’ heart rates as measured by a true electrocardiogram (ECG) and are “highly inaccurate during elevated physical activity.”

Fitbit Blaze, Charge HR, and Surge Heart Rate Monitors

Fitbit advertises its heart monitors as the most accurate wrist-worn wireless tracking devices on the market. Fitbit claims to have conducted “multiple internal studies to rigorously test” the accuracy of the wrist-mounted monitors.

The Fitbit Charge HR is an enhanced version of the Fitbit Charge activity tracker wristband that adds continuous heart-rate monitoring. Fitbit claims the Charge HR allows users to “maintain workout intensity, maximize training, and optimize health.”

The Fitbit Surge retails for about $100 more than the Charge HR. It is part smartwatch, part GPS running watch and includes all-day heart-rate tracking. Fitbit promotes the Surge as the “ultimate fitness superwatch” that allows athletes to maximize their training by keeping them “in the zone” and without “guessing” one’s heart rate.

Importance of Accuracy in Fitness Heart Rate Monitors

Heart rate monitors are used by athletes and others who need to reach or not exceed target heart rates. The use of monitors reporting inaccurate heart rates can lead to serious consequences.

As explained in a review of these devices by, “Heart rate training relies on exercising in different heart rate zones – each of which is a percentage of your maximum heart rate and stimulates different metabolic pathways and has different effects on the enzymes in the muscles. Once you know your zones, you can schedule workouts to make the greatest fitness gains without overworking your body, that is, if you are measuring the zones correctly.”

Consumer Complaints That Fitbit Heart Rate Monitors Are Defective Devices

As noted above, on January 5, 2016 consumers from California, Colorado, and Wisconsin filed a nationwide class action lawsuit against Fitbit, Inc. alleging that Fitbit’s wrist-based “Charge HR” and “Surge” heart rate monitors do not and cannot consistently record accurate heart rates during the intense physical activity for which Fitbit expressly markets the devices in widespread advertising. The suit contends — and expert testing confirms — that the Heart Rate Monitors consistently mis-record heart rates by a significant margin, particularly during intense exercise. Not only are accurate heart readings important for those engaging in fitness, they can be critical to the health and well-being of people whose medical conditions require them to maintain (or not exceed) a certain heart rate.

Prior to the suit’s filing, consumers complained on online review sites and other forums that the Fitbit heart rate monitors were flawed because they provided unreliable heart rates readings when user were exercising.

These complaints were made by athletes who simultaneously tested their heart rates using the Fitbit devices and other types of heart rate monitors. In numerous instances, the consumers stated that their FitBit device gave heart rate readings during their exercise routines that were 20-50% less than the heart rates measured by these other devices.

Submit Your Fitbit Complaint

If you purchased the Fitbit Charge HR or Fitbit Surge for monitoring your heart rate, we welcome the opportunity to learn of your experience with the device. We will review your claim for free, confidentially, and with no obligation on your part.

We will respond to your inquiry as promptly as possible. There is no charge or obligation for our review of your case. Please note that completion of this form cannot contractually obligate plaintiffs’ attorneys to represent you. We can only serve as your attorney if you and we both agree, in writing, that we will serve as your counsel.

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About Consumer Law

State and federal laws provide consumers with remedies for products that are defectively designed or manufactured, or which do not perform as advertised. In many cases, consumers can benefit from such laws even after a warranty period has expired.

The cost for a consumer to hire an attorney and file an individual lawsuit against the manufacturer of a defective product is often prohibitive. The law, however, does not leave the consumer powerless.

A small number of consumers may file a class action lawsuit, representing all consumers who purchased the defective product. A class action suit can provide a powerful and effective means for consumers to compel a corporation to acknowledge its legal responsibilities and provide just compensation to the class members.

About Lieff Cabraser

Recognized as “one of the nation’s premier plaintiffs’ firms” by The American Lawyer, Lieff Cabraser has successfully litigated and settled hundreds of class action lawsuits, including dozens of cases requiring manufacturers to refund the cost of worthless and defective products or costs the consumer incurred in repairing them, to fix the defects, and to extend consumer warranties.

Trademark Notice

Fitbit, Fitbit Charge HR, and Fitbit Surge are registered trademarks of Fibit, Inc. The use of these trademarks is solely for company and product identification and informational purposes. Fitbit, Inc. is not in any affiliated with Lieff Cabraser Heiman & Bernstein, LLP. Nothing on this website has been authorized or approved by Fitbit, Inc.