About JetLagPlanner
JetLagPlanner is a free set of travel timing tools: a flight time calculator, a time zone converter, and a jet lag adjustment planner. It exists because the same three questions come up before every long-haul trip — how long is the flight, what time will it be when I land, and how wrecked will I feel — and answering them usually means three different sites.
What the tools do
- Flight Time Calculator — great-circle distance and estimated flight duration between any two airports in our database.
- Time Zone Converter — the live time difference between two cities, resolved against the current daylight saving rules.
- Jet Lag Planner — a day-by-day light exposure and sleep timing schedule based on the zone shift and direction of your flight.
- Route Directory — precomputed pages for thousands of airport pairs, each with distance, duration, and time difference.
- Travel Guides — longer reads on jet lag recovery, long-haul comfort, and destination timing.
Privacy
Every calculation runs client-side in your browser. Airport coordinates and time zone identifiers ship with the page, and time zone maths uses your browser's own internationalisation engine. No route, date, or sleep information is transmitted to a server, and there is no account to create.
The site is supported by display advertising, which is why you will see ad slots on subpages. Ad providers set their own cookies; the tools themselves do not require any.
Accuracy and limitations
Flight durations are physics-based estimates from great-circle distance and a typical cruise profile, not airline schedule data. Real flights differ because of routing, winds, air traffic control, and taxi time. Jet lag output is a population-level estimate drawn from circadian research, not personalised medical advice — if jet lag seriously affects your health or work, speak to a clinician.
The full set of formulas and data sources is documented on the methodology page.
Languages
The tools, route pages, and guides are fully available in English, German, French, and Spanish, served from /de/, /fr/ and /es/.