Does this include waking up during the night?

No. The estimate subtracts only your chosen time to fall asleep. Overnight awakenings are not measured and would reduce your actual sleep.

What if bedtime and wake-up time are the same?

You choose: the same clock time can mean a full 24 hours in bed, or 0 hours if both times refer to the same moment.

Is the estimated duration my actual sleep?

No. It is a clock-time estimate of how long you could sleep between bedtime and wake-up, minus your time to fall asleep. It is not a measurement.

Sleep Duration Calculator

Calculate your time in bed and estimated sleep duration.

Hours between bedtime and wake-up

Bedtime

Wake-up time

Time to fall asleep

Time in Bed

8 h

Estimated Sleep Duration

7 h 45 min

Sleep Start Time

11:15 PM

Wake-up is the next day. The estimate subtracts your chosen 15 minutes to fall asleep — it does not subtract overnight awakenings and is not a measurement of actual sleep.

How this calculator works

The calculator counts the minutes between your bedtime and your wake-up time. If the wake-up time is earlier than the bedtime, the calculation crosses midnight. From the total time in bed it subtracts your chosen time to fall asleep, which gives the estimated sleep duration.

This is a clock-time estimate. It does not subtract awakenings during the night, and it does not measure sleep stages or sleep quality.

Questions about sleep duration

Does this include waking up during the night?: No. The estimate subtracts only your chosen time to fall asleep. Overnight awakenings are not measured and would reduce your actual sleep.
What if bedtime and wake-up time are the same?: You choose: the same clock time can mean a full 24 hours in bed, or 0 hours if both times refer to the same moment.
Is the estimated duration my actual sleep?: No. It is a clock-time estimate of how long you could sleep between bedtime and wake-up, minus your time to fall asleep. It is not a measurement.