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Both calculators run independently — change the inputs on either side to compare results.

Jet Lag Recovery Calculator

Estimate the number of days needed to fully resync your circadian rhythm after long-haul travel, weighted by time-zone shift, direction (eastward is harder), age, and travel frequency. Use it before a trip to plan meetings and downtime realistically.

Time Zone Difference (hours)

Travel Direction

Age (years)

Travel Experience

Fill in the required fields to see your result.

Time Zones

Circadian Rhythm Adjustment Calculator

Estimate your adjusted bedtime target when shifting your sleep schedule across time zones before or after travel. Helps frequent flyers and shift workers gradually phase-shift their circadian clock to minimize jet lag.

Current Time Zone (UTC offset)

Target Time Zone (UTC offset)

Current Bedtime (h)

Pre-travel Adjustment Days (days)

Light Sensitivity

Fill in the required fields to see your result.

Key differences

	Jet Lag Recovery Calculator	Circadian Rhythm Adjustment Calculator
Category	Time Zones	Time Zones
Inputs required	4	5
Result	Recovery Time (days)	Recommended Bedtime Adjustment (hours)
What it does	Estimate the number of days needed to fully resync your circadian rhythm after long-haul travel, weighted by time-zone shift, direction (eastward is harder), age, and travel frequency. Use it before a trip to plan meetings and downtime realistically.	Estimate your adjusted bedtime target when shifting your sleep schedule across time zones before or after travel. Helps frequent flyers and shift workers gradually phase-shift their circadian clock to minimize jet lag.