About the Jet Lag Calculator
The Jet Lag Calculator exists to answer one question precisely: given this flight and these sleep hours, what should I do and when should I do it?
What the tool is for
Most jet lag advice is general. Drink water, avoid alcohol, get some sunlight. None of it tells a traveller which hour to seek that sunlight, and the hour is the entire point. Light at 06:00 helps one traveller and harms another, depending on where their body clock currently sits.
This tool replaces the general advice with a dated schedule. It takes a route, a pair of flight times and a habitual sleep window, and returns the specific hours that move your clock towards local time at your destination.
How it is built
| Airports held | 3,244 with scheduled passenger service |
|---|---|
| Countries covered | 233 |
| Distinct time zones | 364 IANA zone identifiers |
| Airport data source | OurAirports, released into the public domain |
| Time zone resolution | Platform tz database, resolved per instant |
| Where calculation runs | Entirely in the visitor browser |
| Data stored on a server | None |
| Account required | None |
| Cost | Free |
The site is a static build. There is no backend, no database and no analytics profile attached to your trip. Your route never leaves the device you type it on.
What the tool does not do
The calculator schedules circadian timing. It does not diagnose, treat or replace advice from a clinician. It does not account for individual chronotype, for a pre existing sleep disorder, or for medication that affects sleep and alertness.
It also does not remove the sleep debt a long flight creates. Light and melatonin timing move the clock. Only sleep repays sleep.
Getting in touch
Corrections, data problems and feature requests are all welcome. Write to hello@jet-lag-calculator.com or use the contact page.