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
| 4AM to 8AM | 9AM to 2AM | 2PM to 12AM |
| 8AM to 11AM | 7PM to 12AM | 12AM to 2PM |
| 8PM to 7PM | 12PM to 6PM | 9AM to 5PM |
| 9AM to 12AM | 12PM to 7PM | 4PM to 2AM |
| 12PM to 4PM | 6PM to 4AM | 12PM to 1PM |
| 9PM to 10PM | 12PM to 3AM | 3PM to 6AM |
