Time Calculator
Calculate time differences, add multiple time values, and convert units. Useful for work hours, workouts, and travel planning.
Calculate difference between times
h
:m
:s
→
h
:m
:s
Elapsed time8h 30m 00s
Total hours8.5000 h
Total minutes510 m
Total seconds30600 s
Examples
Work hours calculation
Start 09:00 → End 18:30 with a 1-hour lunch break
18:30 − 09:00 = 9시간 30분
After lunch: 9h 30m − 1h = 8h 30m
Time unit conversion
1 hour 30 minutes = 90 minutes = 5,400 seconds
Formula: hours × 60 = minutes, minutes × 60 = seconds
Adding multiple durations
Workout 1h 30m + travel 45m + prep 20m
= 2h 35m
Frequently Asked Questions
How many working hours is 9:00 to 18:00?
18:00 − 09:00 = 9 hours. If you subtract a 1-hour lunch break, that becomes 8 working hours.
How many hours is 3600 seconds?
3600 ÷ 60 ÷ 60 = 1 hour.
How do I handle times crossing midnight?
If a session starts at 23:00 and ends at 02:00 the next day, the actual difference is 3 hours. Add 24 hours to the end time conceptually.
How many seconds are in one day?
1 day = 24 hours = 1,440 minutes = 86,400 seconds.