Time Duration Calculator
Hours and minutes between two times (even overnight), and add or subtract time.
Result
How to use
- 1
Enter a start and end time — if the end is earlier, it is treated as the next day.
- 2
Optionally subtract a break.
- 3
Use the lower section to add or subtract hours and minutes from a time.
Questions
How are overnight shifts handled?
If the end time is earlier than the start time, the calculator assumes the end is on the next day — for example 10:00 pm to 6:00 am is 8 hours.
How do I convert minutes to decimal hours?
Divide the minutes by 60. So 8 h 30 min is 8.5 hours and 7 h 45 min is 7.75 hours — useful for timesheets and overtime.
About this Time Duration tool
Time Duration Calculator — Hours and minutes between two times (even overnight), and add or subtract time. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.
Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Enter a start and end time — if the end is earlier, it is treated as the next day.
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Results are estimates to help you plan. They are not financial, tax or medical advice.