Shift Work Sleep Calculator for Night and Day Shifts

Enter your shift start time, shift length and commute, and the calculator works out your off-duty window and fits sleep into it. If a full night of sleep will not fit, it suggests a main sleep block plus a one-cycle nap.

Worked example

For a 7:00 PM start, 12-hour shift and 30-minute commute, sleeping after work:

How the off-duty window is calculated

The calculator assumes the same shift repeats daily. It removes your commute, a 30-minute wind-down and a 30-minute wake-up routine, then reserves about three hours for meals and personal time. Whatever time is left is your sleep window.

Split sleep for long shifts

After a 12-hour shift there is often room for only four cycles in total. Splitting sleep into a main block and a nap is a common way to get closer to the recommended five to six cycles. Keep the bedroom dark and quiet, since daytime sleep is easily disturbed.

Frequently asked questions

Should I sleep before or after a night shift?

Many people sleep after, then take a short nap before the next shift. The calculator lets you choose either approach and shows the times.

Is split sleep OK?

It can be a practical way to reach enough total sleep when one long block will not fit. If you struggle with sleep or alertness on shift work, talk to a doctor.

Does this work for rotating shifts?

It plans a repeating shift. For rotating schedules, use it for each stretch of the same shift and see our rotating shift guide.

Related guides and tools

• A worked 12-hour night shift sleep schedule
• How to sleep during the day
• Naps before a night shift
• Managing rotating shift work
• What is shift work sleep disorder?

Results are estimates and general information, not medical advice. Talk to a doctor if you have ongoing sleep problems.