Time Calculator

Add and subtract hours, minutes and seconds, or find the clock time a duration from now.

Multiply or divide

4 hours and 15 minutes

H:MM:SS: 4:15:00
Total hours: 4.25
Total minutes: 255
Total seconds: 15,300

Adds and subtracts durations in days, hours, minutes and seconds, and can multiply or divide the total, for timing a set of tasks, splitting a total evenly or scaling one up. The second mode adds a duration to a clock time, or takes it away, and says which day the result falls on.

How to use it

Durations — one row per duration, up to 50; + or − at the start of a row adds or subtracts it. Parts take fractions, so 1.5 in Hours is 1 hour 30 minutes, and need not be within their unit: 90 minutes works. Paste a list to add many rows at once, one duration a line, written as 1:30:15, 1h 30m or 90 min, with a minus sign to subtract.
Multiply or divide the total — to share a total evenly or to repeat a duration. A result that does not come out in whole seconds is rounded to the nearest second, and the tool says so.
Clock time — a time, with seconds, plus or minus a duration. It starts at the current time and follows it live until another time is chosen; Now goes back to it. Without a date the result says whether it is on the same day, the next or another; with a date it gives the full date. Clock time is counted as it reads, so a change for daylight saving is not applied.

Examples

Adding up time spent

Sessions of 2:45, 1:30 and 3:15, less a 50-minute break, come to 6 hours and 40 minutes, or 6:40:00.

Sharing a total evenly

7 hours 45 minutes over 7 days is 1 hour, 6 minutes and 26 seconds a day. The exact share is a fraction of a second longer, so the result is rounded to the nearest second.

A time past midnight

9 hours after 22:30 is 07:30, next day (7:30 am).

Common conversions

A duration in each unit on its own

Duration	Hours	Minutes	Seconds
1 minute	0.0167	1	60
15 minutes	0.25	15	900
30 minutes	0.5	30	1,800
45 minutes	0.75	45	2,700
1 hour	1	60	3,600
1 hour and 30 minutes	1.5	90	5,400
8 hours	8	480	28,800
1 day	24	1,440	86,400
7 days	168	10,080	604,800

Frequently asked questions

An hour has 60 minutes, so the decimal part is a share of 60, not a count of minutes: 0.5 hours is 30 minutes and 0.25 hours is 15 minutes. The same holds the other way: 1:50 is 1.83 hours, to two places.

The total goes below zero and is shown with a minus sign, such as −45 minutes, so a running balance of time owed works the same way as one of time spent.