Wrist skin temperature is usually lower and more variable than core body temperature because the skin is a heat-exchange surface. Heat moves from deeper tissues toward the skin and then to the surroundings, while changes in skin blood flow also affect the temperature measured at the wrist.
Body Temperature - Thermometer reads the wrist skin-temperature sensor on supported Samsung Galaxy Watch models. It does not measure core body temperature, and its result should not be interpreted as an oral temperature or a fever diagnosis.
What is the difference between wrist skin and core temperature?
Core temperature describes temperature in deeper, well-perfused parts of the body. Skin temperature describes the body surface. An NCBI Bookshelf overview of temperature regulation explains that core temperature is higher and more stable, while skin temperature is lower and more variable because of external factors.
Samsung's sensor documentation makes the product distinction equally clear: its skin-temperature tracker reports skin temperature and ambient temperature around the watch, and Samsung states that this is not the same as body temperature.
Why can a wrist reading be lower?
Heat reaches the skin through the circulation and can then leave through radiation, conduction, convection and evaporation. In a cooler environment, the body can also reduce blood flow near the skin. Those processes help protect the core but can leave the wrist surface cooler than deeper tissues.
The exact difference is not a fixed number. Room conditions, airflow and normal changes in peripheral circulation can affect a surface reading. Because these factors can change the gap, this article's safety guidance is not to use a universal offset to treat a wrist value as a clinical core-temperature measurement.
What does the Galaxy Watch app show?
The current Google Play listing says Body Temperature - Thermometer provides one-tap wrist skin-temperature readings, Celsius and Fahrenheit display options, a calibration setting, a Wear OS Tile, complication support and standalone watch operation. The compatibility section currently names these models:
- Galaxy Watch 5 and Watch 5 Pro
- Galaxy Watch 6, Watch 6 Classic and Watch 6 Classic Astro Edition
- Galaxy Watch 7
- Galaxy Watch 8 and Watch 8 Classic
- Galaxy Watch Ultra and Galaxy Watch Ultra (2025)
The current listing specifically names Samsung Galaxy Watch models and does not name Pixel Watch or another non-Samsung model. Check live device eligibility on Google Play before installing.
Can calibration turn wrist temperature into core temperature?
No. The Google Play listing says the calibration setting can fine-tune readings. It does not describe calibration as a clinical conversion, and calibration does not change the physical measurement site. The result remains wrist skin temperature.
This app is not a medical device and is not intended to diagnose, treat, or prevent fever or any medical condition. Consult a healthcare professional for medical advice, diagnosis or treatment.
For the broader feature and model overview, read Galaxy Watch Wrist Temperature App: Features and Compatibility. A separate wrist skin-temperature measurement guide explains the basic app flow.
Frequently asked questions
Is wrist skin temperature normally lower than core temperature?
It is usually lower and more variable, although the difference is not fixed. Skin exchanges heat with the environment and changes with peripheral blood flow.
Can I add a fixed number to estimate core temperature?
No fixed offset can reliably convert every wrist skin reading into core temperature. Conditions around the wrist and the measurement site itself can change the gap.
Can this app diagnose fever?
No. Body Temperature - Thermometer is not a medical device and is not intended to diagnose, treat, or prevent fever or any medical condition. Consult a healthcare professional for medical advice, diagnosis or treatment.
Where can I check current compatibility?
You can view Body Temperature - Thermometer on Google Play for the models currently named in the compatibility section and the current product limitations.