Hour Converter

There are 3,600 seconds in an hour: 60 minutes of 60 seconds each. The table shows one hour in every unit of the converter.

How Many Minutes in an Hour

An hour has 60 minutes, so half an hour is 30 minutes and a quarter of an hour is 15 minutes. NIST defines the hour as 60 minutes, or 3,600 seconds, for use with SI units.

Why 60 Minutes in an Hour

Counting in 60s goes back to Mesopotamia, where the Sumerians and later the Babylonians used base 60 for arithmetic and astronomy. Sixty is the smallest number that divides evenly by 1, 2, 3, 4, 5 and 6, which made fractions easy, as NIST's Michael Lombardi notes in Scientific American.

A month has between 672 and 744 hours, depending on its length, and the average month in this converter has 730.5 hours, a twelfth of the 8,766 hours in an average year.

How Many Work Hours in a Month

At 40 hours a week, a year of 52 weeks has 2,080 work hours, which is about 173.33 hours a month on average. A real month has between 20 and 23 weekdays, so a given month has between 160 and 184 work hours before holidays. The Time Card Calculator totals real clock-in and clock-out times.

Time sheets and payroll often show hours as a decimal, and the digits after the point are a fraction of an hour, not minutes. So 8.2 hours is 8 hours and 12 minutes, not 8 hours and 20 minutes, because 0.2 × 60 = 12. Likewise 0.75 hours is 45 minutes, and 30 minutes is 0.5 hours, not 0.3.

To turn a clock time such as 7:45 into decimal hours, use the Hours to Decimal Calculator; to go from decimal hours back to hours and minutes, use the Decimal Time Conversion Calculator.

Hours Between Two Times

Many people looking for an hour converter want the hours between two clock times. That is a different job: the Time Difference Calculator finds the time between, say, 9:15 AM and 6:45 PM, and the Hour Countdown Calculator counts the hours between two dates. To write a time in 24 hour form, such as 3 PM as 15:00, use the Military Time Converter.

Single conversions that start from or end in hours, one page per pair of units.

• Hours to Days Converter: 1 day = 24 hours
• Minutes to Hours Converter: 1 hour = 60 minutes
• Seconds to Hours Converter: 1 hour = 3,600 seconds
• Hours to Weeks Converter: 1 week = 168 hours
• Hours to Years Converter: 1 year is 8,766 hours on average

Each converter below shows one amount of time in many units at once, starting from a different unit.

• Day Converter: days to hours, minutes, weeks, fortnights, months and years at once
• Minute Converter: minutes to hours, seconds, days, weeks and more at once
• Seconds Converter: seconds to milliseconds, nanoseconds, minutes, hours and more at once
• Milliseconds Converter: milliseconds to seconds, minutes, microseconds and more at once
• Time Unit Converter: any amount of time in 13 units, from picoseconds to decades