Hours to Days
One hour equals 0.041667 days.
Days = hours ÷ 24
Time Conversion
Common Time Periods
Time Reference Guide
Time Unit Relationships
1 minute = 60 seconds
1 hour = 60 minutes = 3,600 seconds
1 day = 24 hours = 1,440 minutes
1 week = 7 days = 168 hours
1 month = 30.44 days on average
1 year = 365.2425 days on average
1 decade = 10 years
1 century = 100 years
Precision Time Units
Nanosecond: 1 billionth of a second (10⁻⁹)
Microsecond: 1 millionth of a second (10⁻⁶)
Millisecond: 1 thousandth of a second (10⁻³)
Computer processing: Nanoseconds to microseconds
Human reaction time: ~200 milliseconds
Blink of an eye: ~100-150 milliseconds
Interesting Time Facts
• A leap year has 366 days (31,622,400 seconds)
• The average human lifespan is about 700,000 hours
• Light travels around Earth's equator in ~134 milliseconds
• The universe is approximately 13.8 billion years old
Hours to Days Conversion Table
| h | d |
|---|---|
| 1 | 0.0417 |
| 2 | 0.0833 |
| 3 | 0.125 |
| 4 | 0.1667 |
| 6 | 0.25 |
| 8 | 0.3333 |
| 12 | 0.5 |
| 18 | 0.75 |
| 24 | 1 |
| 36 | 1.5 |
| 48 | 2 |
| 72 | 3 |
| 96 | 4 |
| 120 | 5 |
| 168 | 7 |
| 720 | 30 |
About This Conversion
Hours to days divides by 24, and is the conversion behind project estimates, equipment runtimes and battery or shelf-life ratings quoted in hours. A 72-hour cure time is three days; a 500-hour lamp life is under 21 days of continuous use.
Watch the difference between calendar days and working days. A "40-hour" task is 1.67 calendar days at 24 hours a day, but five working days at eight hours a day. Both are correct answers to different questions, so state which day you mean before the number leaves the room.
Frequently Asked Questions
How many days is 72 hours?
72 hours is exactly 3 days.
How many days is 168 hours?
168 hours is 7 days, one full week.
How many days is 100 hours?
100 hours is about 4.17 days.
Is 40 hours five days?
Only in working days at eight hours each. In calendar time, 40 hours is 1.67 days.
Related Conversions
Converting the other way? Days to Hours
Need a different unit? Open the full time converter