Circadian Shift Work Planner

Design a sleep window that protects melatonin and alertness after a night or rotating shift. Provide your shift start, duty length, commute, wind-down routine, and desired sleep duration to get a clock-specific rest block you can build habits around.

Enter the hour your shift begins using 24-hour time—for example, 22 for 10:00 PM.
Total hours on duty including breaks and turnover.
Travel time from worksite to bed, including errands or public transport.
Time required to eat, shower, dim lights, and detach before sleep.
Preferred sleep length for full recovery—fractional hours are welcome.

Educational information, not professional advice.

Examples

  • Shift 19:00, 12-hour duty, 1.0-hour commute, 1.5-hour wind-down, 7.5 hours sleep ⇒ Sleep from 08:30 to 16:00
  • Shift 22:00, 8-hour duty, 0.5-hour commute, 0.75-hour wind-down, 6.5 hours sleep ⇒ Sleep from 07:15 to 13:45
  • Shift 07:00, 10-hour duty, 0.75-hour commute, 1.0-hour wind-down, 7.0 hours sleep ⇒ Sleep from 19:45 to 02:45

FAQ

Can I enter fractional hours?

Yes. Enter decimals such as 1.5 for 1 hour 30 minutes or 0.75 for 45 minutes so the planner captures your true routine.

Does the result specify light exposure timing?

The output provides a sleep range; use it to schedule bright light in the final 30 minutes before wake time and dim light or blue light blockers during the wind-down period.

How should I adjust on days off?

Re-run the planner with your day-off start time or a shortened shift to chart a gradual transition back toward daytime sleep without large circadian shocks.

Will melatonin supplements change the window?

Supplement timing can shift your ideal bedtime by 30–60 minutes. Use the calculator as a baseline and consult a clinician before adding supplements.

How do I adapt on quick turnarounds?

Shorten the wind-down buffer and split the sleep block into two segments—run the planner twice and combine the results to create a core sleep plus a nap.

Can teams share schedules?

Yes. Plug in each crew's shift start and commute assumptions to coordinate overlapping rest windows and minimise noise or light exposure conflicts at home.

Additional Information

  • Use the recommended sleep window to plan blackout curtains, meal timing, and caffeine cutoffs so your circadian rhythm stays anchored.
  • Combine the output with the Sleep Cycle Count calculator to tune your wake-up to a complete 90-minute cycle.
  • If you rotate across time zones, pair this planner with the Jet Lag Recovery tool to coordinate light exposure and melatonin timing.
  • Track how you feel after a week on the schedule and adjust inputs—small tweaks to wind-down or commute buffers can unlock extra rest.

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