Jet lag planner
Beat jet lag with a day-by-day plan.
Pick two cities. We’ll generate a pre-trip bedtime shift, an in-flight strategy, and post-arrival light + melatonin timing — based on the Eastman & Burgess protocol and the Cochrane melatonin review.
Popular routes
- London → New York
- London → Tokyo
- London → Los Angeles
- New York → London
- New York → Tokyo
- New York → Los Angeles
- Tokyo → London
- Tokyo → New York
- Tokyo → Los Angeles
- Los Angeles → London
- Los Angeles → New York
- Los Angeles → Tokyo
- Paris → London
- Paris → New York
- Paris → Tokyo
- Dubai → London
- Dubai → New York
- Dubai → Tokyo
- Singapore → London
- Singapore → New York
- Singapore → Tokyo
- Sydney → London
- Sydney → New York
- Sydney → Tokyo
- Hong Kong → London
- Hong Kong → New York
- Hong Kong → Tokyo
- Berlin → London
- Berlin → New York
- Berlin → Tokyo
- San Francisco → London
- San Francisco → New York
- San Francisco → Tokyo
- Chicago → London
- Chicago → New York
- Chicago → Tokyo
How jet lag works
Your circadian pacemaker — the suprachiasmatic nucleus — runs on a roughly 24-hour cycle synced primarily by light. Cross enough time zones and your internal clock disagrees with the local sun. The fix is to re-entrain the clock with three tools: bright light at the right time, darkness or dim light when needed, and (for big eastward jumps) a small dose of melatonin.
Body clocks reliably shift about 1 hour per day. Westward travel (delaying the clock) is generally easier than eastward (advancing it). The plans below scale to the shift size — small shifts get short plans, big shifts get pre-trip preparation.