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Wrist temperature baseline analyzer
Put one wrist-temperature change in the context of several nights from the same device.
Wrist temperature baseline analyzer
Example valuesPut one wrist-temperature change in the context of several nights from the same device.
No account needed. Calculations happen in your browser; your entries are not saved or sent to Century.
Example · Change from recent median
0.30°C
Wrist skin temperature is not core temperature or a fever test.
- Recent median
- 0.00 °C
- Typical variation
- 0.10 °C
How it’s calculated
The recent baseline is the median of previous nightly temperature deviations from the same device. Typical variation is the median absolute deviation from that median. Today’s change is today’s device-reported deviation minus the recent median. This is a secondary trend summary, not an absolute body temperature, fever test or ovulation estimate. Temperature varies with sleep environment, menstrual cycle and other factors.
Reference: Apple: Track nightly wrist-temperature changes
For general wellness information. This tool does not diagnose health conditions or replace medical advice.
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Wrist temperature baseline analyzer: use your own data
What to enter
Put one wrist-temperature change in the context of several nights from the same device.
The median is less affected by one unusual night. The median absolute deviation gives a simple view of typical variation, not a clinical normal range.
Read the result in context
Compare the new deviation with the median of the earlier readings. This is a personal trend, not an absolute body temperature.
Wrist skin temperature is not core body temperature and is affected by the environment and physiology. Use an appropriate thermometer and medical guidance when illness is a concern.
Where this estimate stops
This tool only summarizes manually entered deviations. It does not reproduce a device’s menstrual-cycle algorithm or estimate ovulation.
Follow your overnight trends in Century.
Frequently asked questions
Can I use Apple Watch temperature deviations?
Yes. Enter the signed nightly deviations shown by the same device, all in °C. Do not mix absolute wrist temperatures with deviations or combine different devices.
Why use a median instead of an average?
The median is less affected by one unusual night. The median absolute deviation gives a simple view of typical variation, not a clinical normal range.
Does a higher wrist temperature mean I have a fever?
No. Wrist skin temperature is not core body temperature and is affected by the environment and physiology. Use an appropriate thermometer and medical guidance when illness is a concern.
Can this estimate ovulation?
No. This tool only summarizes manually entered deviations. It does not reproduce a device’s menstrual-cycle algorithm or estimate ovulation.