How to Use Jet Zzz

Jet Zzz is a free, browser-based jet lag planner. Follow these steps to build a personalized day-by-day adjustment schedule for any flight.

Steps

1. Enter every leg of your trip, including departure and arrival cities and times.
2. Set your sleep profile: usual bedtime, wake time, and chronotype.
3. Add fixed activities like meetings or events the schedule must respect.
4. Choose your adjustment speed, destination environment, and prep window.
5. Generate your day-by-day plan with sleep, light, and activity recommendations.
6. Review the conflicts panel to spot any clash with your fixed activities.
7. Export the plan to your calendar (.ics) or PDF and share it.

Frequently asked questions

What causes jet lag?

Jet lag happens when fast travel across time zones desynchronizes your internal circadian clock from the local day-night cycle, leading to fatigue, poor sleep, and reduced concentration.

How long does jet lag last?

Your circadian rhythm shifts roughly one hour per day, so a six-hour time change typically takes several days to fully adjust. Eastward travel is usually harder than westward.

Can a planner actually reduce jet lag?

Yes. A structured plan that times sleep, light exposure, and activity in the days before and after a flight can meaningfully shorten adjustment compared with doing nothing.

Is Jet Zzz free?

Yes. Jet Zzz is completely free to use in your browser. No account is required.