12-hour night shift sleep schedule: four worked examples

The night shift sleep schedule calculator works out these times for your own shift and trip home.

Four 12-hour night shifts, worked out

The table below works out the same plan for four start times, using the night-shift planner's rules and NIOSH's guidance for nurses.

Every row uses the same inputs: a 12-hour shift, a 30-minute trip home, 7 hours of sleep (the bottom of the CDC range for adults) and a 20-minute nap before the next shift. Only the start time changes; the 7:00 PM to 7:00 AM row is the most common 12-hour night. The nap is optional: it is for days when your daytime sleep ends early. If you can sleep on until the nap time, do that instead.

Four 12-hour night shifts, worked out by the night-shift planner

Swipe the table sideways for the rest of the plan.

How each time is worked out

These are the night-shift planner's own rules, so the table and the planner always agree. Bed is the end of the shift plus the trip, because NIOSH's training for nurses says “Go directly to bed when you arrive home.” (source) The alarm adds 15 minutes to fall asleep and the hours of sleep. The nap is worked back from the next shift: the trip, 45 minutes to get ready (our rule), the nap and the time to fall asleep.

Caffeine stops 6 hours before you lie down. That is our rule, set at the top of the 5 to 6 hour caffeine half-life NIOSH gives, so about half of the last cup is still active at bedtime. The light column splits the shift in two, following NIOSH: “You can be more alert if you increase your light exposure during the first half of the shift.” (source)

What a later start costs

NIOSH's advice for the daytime sleep is “The more sleep you get before 2 p.m., the better rested you will be.” (source) The table shows why the start time matters for that: with a 6:00 PM start, all 7 h of sleep falls before 2:00 PM; with a 9:00 PM start, only 4 h 15 min does, and the alarm goes at 4:45 PM. Each hour later the shift starts, up to an hour more of the sleep falls after 2 p.m.

If your shift pattern lets you choose, that is a reason to prefer the earlier start, or a shorter trip home: the planner shows how much a shorter trip moves bedtime. If you cannot choose, a darker, quieter bedroom matters more for an afternoon sleep (see below).

Handover often runs late. If you get home an hour later than in the table after the 7:00 PM shift, the same plan moves: in bed at 8:30 AM, up at 3:45 PM, with 5 h 15 min of sleep before 2:00 PM. Put your real trip home, handover included, into the planner.

Twelve hours is a long shift

NIOSH notes that “shorter shifts (8 hours or less) are better tolerated than longer shifts.” (source) It also reports that the Institute of Medicine recommends that nurses work no more than 12 hours in any 24-hour period, so every row here sits at that limit. The planner adds a drowsy-driving note for shifts this long. NIOSH also warns about sunglasses on the way home: they block the morning light, which helps you sleep later, but that light is also what keeps a very sleepy driver alert. Its advice is to wear them after a night shift only if someone else is driving (source).

On caffeine across a long night, the US FDA cites 400 milligrams a day as an amount not generally linked with negative effects for most adults. NIOSH's own advice is about timing: night shift workers “could consume it at the beginning of the shift but should stop several hours before the shift ends.” (source)

The nap before the next shift

The table uses NIOSH's short nap: waking at about 20 minutes, before deeper sleep, may leave less grogginess, as may a nap of about 90 minutes. NIOSH also lists studies of longer naps before a night shift, 1.5 to 3 hours long, and reports that “Taking a 3-hour nap (2 to 5 p.m.) produced higher alertness during a subsequent night shift” (source). The nap planner times a nap of either length.

Your first night and your days off

These plans are for a run of nights. Before the first one, NIOSH warns against staying up all day: “You may be tempted to stay up all day before your first night shift in a block of night shifts, and then work all night.” (source) A longer afternoon sleep, like the 1.5- to 3-hour naps above, is the alternative; the nap planner times it. On days off, NIOSH suggests a compromise that keeps part of your sleep at the same hours: go to bed between 3:00 and 4:00 AM and sleep until noon or 1:00 PM, so the morning hours stay a sleep time on work days and days off alike.

Making a daytime sleep work

NIOSH asks for a bedroom that is “very dark (so dark you cannot see your hand in front of your eyes)” (source), or an eye mask, and the AASM's Sleep Education site adds “Make your bedroom quiet and relaxing. Keep the room at a comfortable, cool temperature.” In practice that means:

• blackout curtains or a blind, or a blanket over the window for now;
• the phone on do-not-disturb, and the doorbell or deliveries covered by someone else;
• a household that knows your sleep window: put the bed and alarm times from the table on the fridge;
• the same window on your work nights, so your body knows when the day sleep comes.

Sleeping through the day with traffic outside? Put on a steady fan or brown-noise sound in the Lull app, and it stops a minute before your phone's alarm.

Frequently asked questions

Sources

1. CDC/NIOSH — Training for Nurses, Module 9: Coping with the Night and Evening Shifts, Sleep2020 · read on 2026-10-05
2. CDC/NIOSH — Training for Nurses, Module 9: Coping with the Night and Evening Shifts, Light2020 · read on 2026-10-05
3. CDC/NIOSH — Training for Nurses, Module 6: Prepare for Sleep2020 · read on 2026-10-23
4. CDC/NIOSH — Training for Nurses, Module 6: Sleep Aids and Stimulants, Caffeine2020 · read on 2026-10-05
5. CDC/NIOSH — Training for Nurses, Module 7: Nap Duration2020 · read on 2026-10-05
6. CDC/NIOSH — Training for Nurses, Module 7: Napping Before Nights2020 · read on 2026-10-05
7. CDC/NIOSH — Training for Nurses, Module 5: Guidelines for Designing Work Schedules2020 · read on 2026-10-05
8. CDC/NIOSH — Training for Nurses, Module 5: Extended Shifts2020 · read on 2026-10-05
9. CDC/NIOSH — Training for Nurses, Module 9: Coping with the Night and Evening Shifts, Sleep (continued)2020 · read on 2026-10-16
10. CDC/NIOSH — Training for Nurses on Shift Work and Long Work Hours, Module 8: Relaxation Techniques2020 · read on 2026-10-05
11. CDC/NIOSH — Training for Nurses, Module 6: Do You Have Symptoms of a Sleep Disorder?2020 · read on 2026-10-05
12. CDC — About Sleep (recommended hours by age)2024 · read on 2026-10-23
13. US FDA — Spilling the Beans: How Much Caffeine Is Too Much?2024 · read on 2026-10-05
14. American Academy of Sleep Medicine (Sleep Education) — Healthy Sleep Habits2026 · read on 2026-10-23