About Jet Lag Recovery Calculator
Scientifically plan your circadian rhythm transition when crossing international time zones. Calculates recovery duration based on eastward vs westward flight direction, and provides an actionable 4-day protocol for sunlight exposure, sleep shifting, and caffeine cutoffs.
Key Capabilities & Features
- Asymmetric circadian adjustment modeling: Westward travel (phase delay, 1.5h/day) vs Eastward travel (phase advance, 1.0h/day)
- Actionable 4-day adaptation protocol: Light exposure windows, darkness requirements, melatonin dosing, and caffeine cutoffs
- Target wake and bedtime adjustment schedules to acclimate faster to local destination time
- Sleep hygiene and hydration recommendations for transmeridian flights
How to Use Jet Lag Recovery Calculator
Select Origin Timezone
Choose home origin timezone (UTC offset).
Select Destination Timezone
Choose destination timezone (UTC offset).
Review Recovery Days
Inspect total time difference and estimated days required for full natural circadian adaptation.
Follow 4-Day Protocol
Read daily morning sunlight, evening darkness, and sleep shift schedules.
Privacy & In-Browser Execution Guarantee
100% client-side calculation. Your data never leaves your browser.
Frequently Asked Questions
Why is jet lag worse flying east than flying west?
The human circadian clock has a natural period slightly longer than 24 hours (about 24.2 hours). Lengthening your day by traveling west is easier for the brain than shortening your day by traveling east.
When should melatonin be taken for jet lag?
When traveling eastward, taking 0.5mg to 3mg of melatonin 30 to 60 minutes before your desired bedtime in the new time zone helps advance your circadian sleep rhythm.