Time Duration Calculator · Practical guide
How Many Hours of Sleep Did I Get?
Enter your bedtime and wake time above — the calculator handles the midnight crossover and totals your night.
At a glance
The Quick Answer
If you went to bed at 11:15 PM and woke up at 6:45 AM, you slept 7 hours 30 minutes. Because sleep almost always crosses midnight, keep the assume-next-day option on: the calculator adds 24 hours to the wake time before subtracting.
Interactive tool
Time Duration Calculator
Enter your own values, then compare the result with the examples below.
Results
Worked Example
- Bedtime 11:15 PM → 23 × 60 + 15 = 1,395 minutes
- Wake time 6:45 AM → 6 × 60 + 45 = 405 minutes
- 405 + 1,440 = 1,845 (crossing midnight)
- 1,845 − 1,395 = 450 minutes = 7 h 30 m
Bedtime Lookup for a 6:30 AM Wake-Up
| Bedtime | Wake 6:30 AM | Sleep |
|---|---|---|
| 9:30 PM | 6:30 AM | 9 hours |
| 10:30 PM | 6:30 AM | 8 hours |
| 11:30 PM | 6:30 AM | 7 hours |
| 12:30 AM | 6:30 AM | 6 hours |
How Much Sleep Do You Need?
The CDC recommends at least 7 hours per night for adults, 8-10 hours for teenagers, and 9-12 hours for school-age children. If the calculator shows you're regularly under 7 hours, shifting bedtime 30-60 minutes earlier is the easiest fix — each half hour of earlier bedtime adds a full 30 minutes to your night.
Frequently Asked Questions
How much sleep did I get from 11 PM to 6 AM?
7 hours. Enter 23:00 as the start and 06:00 as the end with the next-day option on to see it in minutes and seconds too.
Do naps count toward total sleep?
Yes. Add the nap duration to your nighttime total — a 6 h 30 m night plus a 30-minute nap gives you 7 hours for the day.
Is 6 hours of sleep enough?
For most adults, no. Guidelines call for at least 7 hours; regularly sleeping 6 hours is linked to reduced alertness and long-term health risks.
What if my wake time is after noon?
The calculator handles any same-cycle span. Sleeping 2:00 AM to 11:30 AM computes as 9 hours 30 minutes with the next-day option enabled.