ReferenceExcel FormulasSupported FormulasHOUROn this pageHOUR The HOUR function returns the hour component of a time value (0-23). Syntax =HOUR(serial_number) Parameters serial_number: The time value from which to extract the hour Examples =HOUR("13:45") // Returns 13=HOUR("9:30 AM") // Returns 9=HOUR(0.75) // Returns 18 (0.75 of a day = 18:00)