Time Calculator

Which tool should I use?

• Time Calculator (this page): add and subtract lengths of time, or find the time between two clock times.
• Time Converter: convert a length of time from one unit to another, such as seconds to hours.
• Date Calculator: find the date that is a number of days, weeks, months or years from a date.
• Days Between Dates Calculator: count the days between two dates.

Elapsed time and clock time

• Elapsed time is a length of time, such as 1 hour 45 minutes. You can add and subtract elapsed times. Totals above 24 hours are shown as they are (25 hours stays 25 hours).
• Clock time is the time shown on a clock, such as 9:00 or 22:30. You do not add clock times; you find the difference between two of them.

How it works

• Add or subtract elapsed time: each row is converted to seconds, rows marked + are added and rows marked − are subtracted, and the total is shown in hours, minutes and seconds. If subtracting makes the total negative, the result is shown with a minus sign.
• Time between two clock times: end time − start time. If the end time is earlier than the start time, the end is counted as the next day, so 22:00 to 6:30 is 8 hours 30 minutes. If the two times are the same, the difference is 0.

Examples

• 1 h 45 min 30 s + 2 h 30 min 45 s + 50 min = 5 h 6 min 15 s (5.1042 hours).
• 8 h − 2 h 15 min = 5 h 45 min.
• 9:00 to 18:30 is 9 hours 30 minutes.
• 22:00 to 6:30 the next morning is 8 hours 30 minutes (crossing midnight).

Notes

• Enter up to 9,999 hours per row, and 0 to 59 for minutes and seconds.
• The difference between clock times ignores dates. If two times are a day or more apart, use "Add or subtract elapsed time" and include the full days (for example, 24 hours).
• Decimal hours are the minutes and seconds converted to hours (1 h 30 min is 1.5 hours). Decimal values are rounded to 4 decimal places for hours and 2 for minutes.
• The result uses the format "h min s" (hours, minutes, seconds). All calculations use whole seconds, so there are no rounding errors.

Frequently asked questions

How do I convert 1 hour 30 minutes to decimal hours?

Divide the minutes by 60 and add them to the hours: 1 + 30 ÷ 60 = 1.5 hours.

How are totals over 24 hours shown?

They are not wrapped at 24 hours. For example, 25 hours 10 minutes is shown as 25 h 10 min.

How is a time that crosses midnight counted?

When the end time is earlier than the start time, it is counted as a time on the next day. From 22:00 to 6:30 is 8 hours 30 minutes.

What happens if I subtract more time than I add?

The result is negative and is shown as a negative time.