Jet Lag Light Exposure Planner
Builds a day-by-day plan for shifting your body clock to a new time zone using the strongest lever there is — light. From your home and destination UTC offsets and your usual sleep hours it works out whether to advance or delay your clock, then times the bright-light, light-avoidance and melatonin windows around your body-temperature minimum for each day of the adjustment, all in destination local time.
Read the full guide to this tool
Results
Notes
- The body clock shifts about 1.5 h/day when advancing (travelling east) and up to 2 h/day when delaying (travelling west), so eastward trips are harder.
- Light timing is keyed to your body-temperature minimum, roughly 2–3 h before your usual wake time: seek light just after it to advance, just before it to delay, and avoid light on the wrong side. Offsets ignore daylight saving.
- This is an educational estimate, not medical advice; consult a professional for decisions about your health.
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