Time Calculator

Time difference, add/subtract duration, and convert hours ↔ minutes ↔ seconds.

Start date

Start time (optional)

End date

End time (optional)

Duration, time difference, and unit conversion.

Compute time between two times or dates, add/subtract time, and convert between hours, minutes, and seconds.

Duration between two clock times in hours, minutes, and seconds.E.g. 09:00 to 17:30 is 8 hours 30 minutes.
Date-difference mode gives the number of days between two dates.E.g. 2025-01-01 to 2025-03-01 is 59 days.

UTC (Coordinated Universal Time): UTC is the primary time standard. Local times are often given as UTC offset (e.g. KST = UTC+9).
Duration: Duration is the length of time between two instants, used for work hours, study time, travel time, etc.