News Devices 06-06-2025 at 13:43 comment views icon

Apple Watch counts calories «randomly» — researchers found an error of 30%, which is three times (!) higher than normal

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Kateryna Danshyna

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Apple Watch counts calories «randomly» — researchers found an error of 30%, which is three times (!) higher than normal

Despite the fact that Apple smartwatches offer highly accurate measurements of heart rate and step counts, they are virtually «at random with calorie counting».

The last research University of Mississippi (via MacRumors) found that the error in estimating calories burned with Apple Watch reaches 27.96% — more than three times the allowable rate. It was the same for different models (even the newest ones), all users who participated in the studies, and during different types of physical activity. For comparison: errors in measuring heart rate and number of steps with Apple Watch reach 4.43% and 8.17%, respectively and are within the threshold acceptable for consumer fitness devices.

It is noted that for the study, the team examined 56 previous reports that evaluated the effectiveness of the Apple Watch compared to gold-standard clinical instruments.

Apple does not publish the algorithms used in tracking Apple Watch performance, but it also does not claim that the device provides clinical-grade energy consumption measurement. The company has consistently positioned the device as a general wellness tool rather than a medical diagnostic device, although in recent years it has introduced several advanced health features, such as body temperature monitoring and detection of sleep apnea.

In conclusion, the researchers note that they did not intend to discredit manufacturers or the usefulness of smartwatches, but rather advise to clarify the limitations and inform users.

«These devices are great for tracking habits and keeping you motivated. But don’t take every number as 100% true, especially calories. Think of it as a helpful guide, not a diagnostic tool. It’s useful, but not perfect», — the command summarizes

Apple’s annual developer conference, WWDC 2025, starts this Monday, where the company is expected to present changes to its operating systems iOS, iPadOS, macOS, watchOS, tvOS, and visionOS, special gaming application, new AirPods features and probably a Mac Pro with an M4 chip and a smart device for the home.



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