✈️ Jet Lag Recovery Calculator for 12 Time Zones
How long will it take to feel normal again after your flight?
Quick answer
Crossing 12 time zones typically takes around 12 days to fully recover from, travelling eastbound. Westbound is usually a bit quicker.
- Eastbound: ~12 days
- Westbound: ~8 days
- Shift sleep by 1h/day before you travel
- Get morning daylight on arrival
In detail: Jet Lag Recovery Calculator for 12 Time Zones
Crossing 12 time zones typically takes around 12 days to fully recover from, travelling eastbound. Westbound is usually a bit quicker. That's the core number — but the useful context is how sensitive it is to the inputs. Change any one of the assumptions by even 10–20% and the final figure can move meaningfully, which is why a calculator like this is better than a rule-of-thumb memorised from a magazine article.
Looking at the alternate scenarios below, the spread tells you how robust (or fragile) your answer is: if small changes produce big swings, plan for the pessimistic case; if it's stable across the range, you can commit more confidently.
What this tool helps with
Estimated recovery time in days
What you can enter
- Time zones crossed: 12
- Travel direction: East (e.g. US to UK)
Why this page is useful
How long will it take to feel normal again after your flight? This page loads fast, gives a direct answer, and then expands with useful context instead of burying the result under filler.