Convert Days to Hours
Convert Days to Hours instantly. 1 Day (d) equals 24 Hours (h).
Days to Hours conversion table
| Days (d) | Hours (h) |
|---|---|
| 1 d | 24 h |
| 2 d | 48 h |
| 3 d | 72 h |
| 5 d | 120 h |
| 10 d | 240 h |
| 20 d | 480 h |
| 50 d | 1,200 h |
| 100 d | 2,400 h |
| 500 d | 12,000 h |
| 1,000 d | 24,000 h |
1 Day = 24 Hours · multiply Days by 24
About converting Days to Hours
Days (d) and Hours (h) are both units of time, so converting between them is a single multiplication: multiply your Days figure by 24. Ten Days comes to 240 Hours, and a hundred works out at 2,400 Hours.
Rule of thumb: going from Days to Hours multiplies, so the figure always grows — one Day is already 24 Hours. If your answer came out smaller, you have the conversion the wrong way round.
What is a Day?
A day is exactly 86,400 seconds — and that is a statement about the unit, not about the Earth. A real solar day varies slightly depending on winds, tides and what the planet’s core is doing, and tidal friction is gradually lengthening it. The gap between the tidy unit and the untidy planet is what leap seconds patch over. Astronomers also distinguish the solar day from the sidereal day, one full rotation relative to the stars, which is about four minutes shorter because the Earth has meanwhile moved along its orbit.
What is a Hour?
An hour is sixty minutes, and the twenty-four-hour day it divides comes from ancient Egypt, though the sixty inside it is Babylonian. For most of history hours were not equal: daylight was split into twelve parts and the night into twelve more, so an hour was simply longer in summer than in winter. Only mechanical clocks made fixed hours practical, since a clock cannot easily be told to run slower in December. The hour is not an SI unit but is accepted for use with SI, and it remains the unit almost all paid work is priced in.
To put both in perspective: a day is one turn of the Earth on its axis, while an hour is a standard slot in most people’s calendars.
The converter above updates as you type, and the table lists common values for quick reference. Need the opposite direction? Use the Hours to Days converter, or browse all Time converters.
Frequently asked questions
How many Hours are in one Day?
There are 24 Hours in one Day.
How do I convert Days to Hours?
Multiply the number of Days by 24. For example, 10 Days = 240 Hours.
What is 100 Days in Hours?
100 Days is equal to 2,400 Hours.
How do I convert Hours to Days?
Multiply the Hours value by 0.04167 (or divide by 24).
Is this Days to Hours conversion exact?
Yes, exactly. Both units are fixed against the same base by definition, and 1 Day = 24 Hours is the complete value — nothing is rounded away.
What is a Day?
A day is exactly 86,400 seconds — and that is a statement about the unit, not about the Earth. A real solar day varies slightly depending on winds, tides and what the planet’s core is doing, and tidal friction is gradually lengthening it. The gap between the tidy unit and the untidy planet is what leap seconds patch over. Astronomers also distinguish the solar day from the sidereal day, one full rotation relative to the stars, which is about four minutes shorter because the Earth has meanwhile moved along its orbit.
What is a Hour?
An hour is sixty minutes, and the twenty-four-hour day it divides comes from ancient Egypt, though the sixty inside it is Babylonian. For most of history hours were not equal: daylight was split into twelve parts and the night into twelve more, so an hour was simply longer in summer than in winter. Only mechanical clocks made fixed hours practical, since a clock cannot easily be told to run slower in December. The hour is not an SI unit but is accepted for use with SI, and it remains the unit almost all paid work is priced in.