Full name: hour
Plural form: hours
Symbol: hr
Alternate spelling: hrs
Category type: time
Scale factor: 3600
The SI base unit for time is the second.
1 second is equal to 0.00027777777777778 hours.
Valid units must be of the time type.
You can use this form to select from known units:
The hour was originally defined in Egypt as 1/24 of a day, based on their duo-decimal numbering system (which counted finger joints on each hand).
hours to Julian year
hours to lunar year
hours to quarter
hours to century
hours to tropical month
hours to Julian month
hours to sidereal year
hours to millennium
hours to microsecond
hours to decade