A Whoop patent application describes using the clip-on PowerPack battery to calibrate an estimate of core body temperature, a reading current Whoop bands do not give. The method would probably need to accurately measure heart rate and the temperature flux across the device (like GreenTEG Core)
- The application, titled “Core Body Temperature”, was published on 22 October 2026 as US 2026/0324983 (application 19/655,308).
- It describes several temperature sensors, with one near the skin and another inside the removable PowerPack.
- While the band charges, the PowerPack supplies a controlled amount of heat, and the change in temperature is used to model how heat moves through the band and the body beneath it.
- The calibration values from charging are stored and later combined with skin temperature and estimated heat flow to estimate core temperature.
- The filing describes collecting this data during ordinary charging, so the PowerPack does not need to be worn all day.
What it means for athletes
If it reaches product, a Whoop band could show core temperature during long sessions and heat training, which today requires a dedicated sensor like CORE 2. Whoop currently reports skin temperature as an overnight trend against the wearer’s baseline, as covered in the Whoop 5.0 and MG review.
This is a patent application, and Whoop has not announced a core temperature feature. Any wrist estimate’s accuracy would need independent testing. Current models are on the Whoop 5.0 and MG specs page, and the best recovery tracker guide compares the alternatives.
Quick answers
Does Whoop measure core body temperature?
No. Whoop bands report skin temperature. A patent application published on 22 October 2026 describes a way to estimate core temperature, but Whoop has not announced the feature.
How would the Whoop PowerPack help estimate core temperature?
According to the application, the PowerPack supplies a controlled amount of heat while charging, and sensors measure temperature changes to calibrate a heat-flow model through the band and skin.
The application is listed with the week’s other filings in Trademark & Patent Filing #3, with every issue on the Trademark & Patent Filing hub.
Source and original research by: the5krunner and Gadgets & Wearables
Last Updated on 23 October 2026 by tfk the5krunner
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. See the gear tfk uses. ID
