Units
Time converter
Hours to minutes, days to hours, weeks to days. And the small end too, from milliseconds down to nanoseconds.
Conversions are worked out on your own machine. No sign-up, no waiting and nothing sent anywhere.
Common conversions
| hour | minute |
|---|---|
| 1 h | 60 min |
| 2 h | 120 min |
| 5 h | 300 min |
| 10 h | 600 min |
| 24 h | 1,440 min |
| 30 h | 1,800 min |
| 60 h | 3,600 min |
| day | hour |
|---|---|
| 1 d | 24 h |
| 2 d | 48 h |
| 5 d | 120 h |
| 10 d | 240 h |
| 24 d | 576 h |
| 30 d | 720 h |
| 60 d | 1,440 h |
| week | day |
|---|---|
| 1 wk | 7 d |
| 2 wk | 14 d |
| 5 wk | 35 d |
| 10 wk | 70 d |
| 24 wk | 168 d |
| 30 wk | 210 d |
| 60 wk | 420 d |
| year | day |
|---|---|
| 1 yr | 365.25 d |
| 2 yr | 730.5 d |
| 5 yr | 1,826.25 d |
| 10 yr | 3,652.5 d |
| 24 yr | 8,766 d |
| 30 yr | 10,957.5 d |
| 60 yr | 21,915 d |
| minute | second |
|---|---|
| 1 min | 60 s |
| 2 min | 120 s |
| 5 min | 300 s |
| 10 min | 600 s |
| 24 min | 1,440 s |
| 30 min | 1,800 s |
| 60 min | 3,600 s |
Worked out with the same factors the converter above uses.
Time has the roundest and least arguable factors of any category — right up until you reach the month and the year, where there stops being a single answer. The lower rungs are exact by definition: 60 seconds to a minute, 60 minutes to an hour, 24 hours to a day and 7 days to a week, with no exceptions.
The year is another matter. This tool uses the Julian year of exactly 365.25 days, which is what astronomy uses and what makes the light-year meaningful. The Gregorian calendar year is 365 days, or 366 in a leap year, and the tropical year — the time Earth takes to return to the same point relative to the equinox — is 365.2422 days. For everyday sums the difference is negligible; for ephemerides it is not.
The month is frankly a convention: here it is one twelfth of a Julian year, about 30.44 days. There is no way for it to be exact when real months run from 28 to 31 days. That is why month, year, decade and century are all flagged as approximate: the tool says so rather than feigning precision.
Every unit in this category
Frequently asked questions
How many seconds are in a day?
86,400 seconds. Exactly: 24 × 60 × 60. Apart from the very rare days carrying a leap second, which add one.
How many days does a year have in this tool?
365.25, the Julian year, which is the astronomical standard. If you need the exact calendar year, use 365 or 366 as appropriate.
Why is the month flagged as approximate?
Because there is no exact month: they run from 28 to 31 days. This uses one twelfth of a Julian year (30.44 days), which is the sensible choice for a general calculation but no good for counting legal deadlines.