Skin temperature deviation from baseline Fitbit
How to read this. Fitbit measures your wrist temperature during sleep and compares it against your personal 30-day rolling baseline. This chart shows the nightly deviation — not your absolute temperature.
Above +0.5°C — early illness or inflammation, often 24–48h before symptoms appear.
+0.2 to +0.5°C — mild elevation, watch the next 1–2 nights.
–0.3 to +0.2°C — normal variation.
Below –0.3°C — cooler than baseline, not a concern.