Jet Lag Calculator
Calculate your expected jet lag recovery time and get personalized adjustment strategies. Learn the best times for light exposure, when to use melatonin, and how to minimize jet lag symptoms based on your travel direction and time zones crossed.
How many days will you stay at your destination?
How long does jet lag last?
Jet lag typically lasts about 1 day per time zone crossed. However, eastward travel can take 50% longer to recover from than westward travel. For example, traveling 6 time zones east may take 9 days to fully recover, while 6 time zones west takes about 6 days. Recovery depends on age, health, and how well you follow adjustment strategies.
Why is eastward travel harder for jet lag?
Eastward travel is harder because you're shortening your day, which goes against your body's natural tendency to have a slightly longer than 24-hour cycle. Most people find it easier to stay up late (westward) than to wake up early (eastward). Our circadian rhythm naturally runs about 24.2 hours, making it easier to delay sleep than advance it.
What is the best way to prevent jet lag?
Start adjusting your sleep schedule 3 days before departure by shifting 1-2 hours per day toward your destination time. Get bright light exposure at the right times (morning for eastward, evening for westward). Stay hydrated, avoid alcohol, set your watch to destination time immediately, and force yourself onto the local schedule upon arrival.
Does melatonin help with jet lag?
Yes, melatonin can help with jet lag when used correctly. Take 0.5-5mg of melatonin 2 hours before your desired bedtime at your destination for eastward travel. For westward travel, take it at your new bedtime for 2-3 days. Melatonin helps reset your circadian rhythm but should be combined with proper light exposure for best results.
Should I adjust to local time for a short trip?
For trips shorter than your recovery time (typically less than 3-4 days for significant time zone changes), it may be better to stay on your home schedule if possible. Your body won't have time to fully adjust before you return home. For longer trips (1 week or more), definitely adjust to local time.
How does light exposure help with jet lag?
Light is the most powerful time cue for your circadian rhythm. For eastward travel, get bright light exposure in the early morning (6-10 AM) to advance your clock. For westward travel, get bright light in the evening (4-8 PM) to delay your clock. Avoid bright light at opposite times. Even 30 minutes of bright light can significantly help adjustment.
What are the symptoms of jet lag?
Common jet lag symptoms include insomnia or disrupted sleep, daytime fatigue, difficulty concentrating, stomach problems, general malaise, mood changes, and reduced physical performance. Symptoms are typically worse after eastward flights and when crossing 5 or more time zones. Most symptoms resolve as your circadian rhythm adjusts to the new time zone.