Estimate how many days your body needs to adjust after crossing time zones.
Jet lag is the mismatch between your body clock and the local time after crossing time zones. The rule of thumb is one day of adaptation per hour of difference, but eastward travel is harder because your body's natural cycle is slightly longer than 24 hours, so advancing the clock (earlier bedtime) is harder than delaying it.
This calculator estimates the adaptation period based on the timezone difference. It does not account for individual variation, age, or strategies like light exposure and melatonin timing — but it gives a realistic baseline for trip planning.
Practical advice: for short trips (1-3 days), it may be better to stay on home time rather than adapt. For longer stays, shift your schedule 1-2 hours per day starting a few days before departure.
Adaptation days ≈ timezone difference × 0.75. Eastward adds ~25% more time.
Yes — your body's natural cycle is about 24.2 hours, so delaying (west) is easier than advancing (east). Most people adapt about 1.5 hours/day going west but only 1 hour/day going east.
Evidence supports it for eastward travel. Take 0.5-3 mg at the destination bedtime, starting the first night.
A stopover in an intermediate timezone can help break the adjustment into smaller steps.
Vai.la turns any URL into a short link with click statistics, QR Code and your own biolink.
Vai.la is not responsible for how the tools are used or for decisions made based on their results.