Shift Worker Circadian Alignment Planner

Rotating between day, evening, and overnight shifts can wreck circadian rhythm. Enter your current and upcoming shift start times, desired sleep length, and the tools you can use (bright light therapy and caffeine timing) to see how quickly you can realign.

Current shift start in 24-hour time (e.g., 22.0 for 10:00 PM).
New shift start in 24-hour time (e.g., 7.0 for 7:00 AM).
Target nightly sleep duration once aligned.
How many days you can dedicate to shifting before the new rota begins.
Leave blank to assume 45 minutes of targeted bright light therapy.
Leave blank to stop caffeine six hours before bedtime.

Wellness aid only. Consult occupational health for individual sleep medicine advice.

Examples

  • Night-to-day rotation: current 22:00, new 07:00, sleep 7.5 h, 7 prep days, default light/caffeine ⇒ Recommended phase shift: 9.00 hours (delay). Adjustment pace: 1.50 hours/day. Required days: 6 (sufficient preparation time). Target bedtime: 23:30. Suggested bright light window: 05:00–06:30.
  • Day-to-late shift with limited prep: current 07:00, new 23:00, sleep 8 h, 4 prep days, 30 min light, caffeine cutoff 4 h ⇒ Recommended phase shift: -8.00 hours (advance). Adjustment pace: 1.08 hours/day. Required days: 8 (short by 3.67 hours of phase shift). Target bedtime: 15:00. Suggested bright light window: 06:00–07:30.

FAQ

How should I schedule meals?

Align meal times with the new shift during preparation—eat your largest meal near the midpoint of the upcoming wake period to reinforce the change.

What if I rotate every week?

Shorten the preparation horizon to the days you actually have and prioritise partial shifts so the residual gap stays manageable.

Can I use this for team scheduling?

Yes. Input team averages for current and future shift start times, then coordinate shared light sessions or caffeine policies based on the output.

Additional Information

  • Adjustment pace accelerates with longer bright-light sessions and slows if caffeine is consumed closer to bedtime.
  • The planner automatically chooses the shorter path (advance or delay) between current and target shifts to protect sleep debt.
  • If residual phase shift remains, use blackout curtains, melatonin, or strategic naps to bridge the remaining hours after the rotation begins.

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