Wake and sleep bands migrating toward destination timeLive current inputs
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Jet Lag Schedule Calculator
Design a pre-travel and post-arrival phase-shift schedule from destination offset, direction, preparation days, planned daily shift, wake time, and sleep opportunity while keeping behavioral timing separate from medical treatment.
Shift completed before travel—
Residual shift on arrival—
Estimated alignment day—
First destination wake target—
First destination bedtime target—
Daily schedule checkpoints—
Protected sleep opportunity—
Preparation coverage—
Body-clock shift grid
Wake and sleep bands migrating toward destination time
Each row is a preparation or arrival day on a 24-hour clock. The wake marker and sleep band move in the selected direction while the destination target remains fixed.
Behavioral timing plan
Day-by-day wake target, sleep window, and residual destination shift
Use the schedule as a communication aid for sleep opportunity and timed routine changes, not as a medication protocol.
| Day | Stage | Wake target | Sleep window | Cumulative shift | Residual shift | Practical focus |
|---|
Schedule setup
Create a behavioral timing plan around the actual trip
- Enter destination shift and travel direction.
- Choose realistic days available before departure.
- Set a tolerable daily routine shift.
- Protect adequate sleep opportunity around the moving wake target.
- Extend arrival-day checkpoints until residual shift reaches zero.
Phase-shift logic
Preparation reduces arrival mismatch but cannot exceed the destination shift
The pre-travel plan accumulates only the smaller of planned adjustment and destination difference. It never overshoots the target clock.
Before travel, an eastward plan moves the home-clock wake target earlier and a westward plan moves it later. At destination, the unadjusted wake point begins displaced by the residual and converges back toward the usual local wake time.
Calculation method
Apply bounded daily phase shifts toward the destination target
Preparation shifts accumulate up to the destination difference. The residual shift on arrival is then reduced at the entered post-arrival rate. Wake time and the preceding sleep window move with the modeled body clock.
Detailed calculation process and general formulas
s_pre = min(Z, P*m/60)Z_0 = max(Z - s_pre, 0)s_j = min(Z, s_pre + j*r)wake_pre,j = wake_home - dir*s_jwake_dest,j = wake_home + dir*(Z - s_j); bed_j = wake_j - HSymbols, meanings, and units
- Z
- absolute destination time shifthours
- P
- number of preparation daysdays
- m
- planned preparation shift per dayminutes/day
- r
- entered post-arrival phase-shift ratehours/day
- H
- protected sleep opportunityhours
Schedule quality
Judge the plan by residual burden and sleep protection
A useful schedule must balance phase progress with sufficient sleep opportunity.
Preparation gain
—Clock shift completed before boarding.
Arrival mismatch
—Destination difference still unresolved at arrival.
First local target
—Modeled destination wake time for the first arrival day.
Alignment horizon
—First modeled day when the full shift is reached.
Decision takeaway: Prefer a smaller repeatable schedule shift with protected sleep over an aggressive plan that creates more sleep loss.
Behavioral safeguards
Keep the schedule practical and non-medical
- Do not reduce sleep opportunity to force a clock shift.
- Adjust work and driving plans if alertness is poor.
- Use local daylight strategically only with reliable guidance.
- Discuss supplements or medication with a clinician.
Schedule evidence
Trip details that improve the plan
- Flight and arrival local times
- Usual sleep window
- Prior direction-specific adaptation
- Required first-day commitments
- Observed sleep and alertness diary
Practical applications
Decisions this calculator is designed to support
Four-day eastward preparation
A traveler advances 45 minutes per day before an eight-hour eastward trip.
What the result clarifies: The shift grid shows the reduced arrival mismatch without sacrificing an eight-hour sleep window.
Short-notice westward trip
A traveler has only one preparation day and relies mainly on post-arrival adjustment.
What the result clarifies: The table makes the larger initial residual and later alignment day explicit.
Worked example
Current-input substitution and reconciliation
Model limitations
This educational schedule models clock timing only. It does not prescribe light treatment, melatonin, medication, meals, naps, or clinical care. Personal circadian response and safe activity decisions can differ materially.
Jet Lag Schedule Calculator FAQ
Can preparation eliminate all jet lag?
Only when the planned cumulative shift reaches the destination difference and real physiology follows the plan.
Why does bedtime appear on the previous clock day?
Bedtime is calculated as wake time minus sleep opportunity and wraps around the 24-hour clock.
Does the model schedule light or melatonin?
No. It provides behavioral wake and sleep targets only.
What if I cannot follow the pre-travel shift?
Reduce preparation days or minutes; the model will carry the remaining mismatch into the arrival schedule.