Jet Lag Calculator

This calculator estimates how long a flight will take to adjust to and lays out a light exposure schedule for each day. Enter the UTC offset at each end, your usual wake and bed times and optionally the arrival date, and it works out the shift your body clock has to make, how many days that takes, and when to seek and avoid bright light at the destination. It uses published rules of thumb: about one hour a day of advance going east, about one and a half hours a day of delay going west, and light windows placed either side of the body temperature minimum. Individual people vary a great deal, and this is schedule arithmetic rather than medical advice.