There are total 21 hours or 1260 minutes from 4am to 1am. In words, this duration is equal to twenty-one hours or one thousand two hundred sixty minutes.
How many hours from
| 3AM to 8PM | 8PM to 10PM | 1PM to 3AM |
| 9PM to 8AM | 8PM to 1AM | 4PM to 3PM |
| 1PM to 7PM | 7PM to 5PM | 1AM to 9PM |
| 12AM to 6AM | 11PM to 1PM | 10PM to 8PM |
| 3PM to 8PM | 2AM to 11PM | 10AM to 8PM |
| 4AM to 12PM | 1PM to 12PM | 5AM to 4PM |
