Enter a number in either field, then select the source and destination units. The other value updates automatically.
60 seconds = 1 minute. 60 minutes = 1 hour. 1 second = 1,000 milliseconds.
Calendar units use fixed approximations: a year is 365 days, a month is 1/12 of that year, and a quarter is 1/4. Use a date calculator for the duration between particular calendar dates.
Fixed time conversions use exact relationships: 60 seconds make 1 minute, 60 minutes make 1 hour and 1 second contains 1,000 milliseconds.
Calendar months and years do not all have the same length. Use a date calculator for an interval between calendar dates, or choose an explicit fixed duration unit for a conversion.
90 minutes equals 1.5 hours. In clock notation that is 1 hour 30 minutes, not 1 hour 50 minutes.
A fixed duration day is 24 hours. A local calendar day around a clock change can have a different elapsed length.
