Event Duration Calculator
How long is the event, and when does it end?
A start and a duration gives the end; a start and an end gives the duration. Both directions, with the time-zone and overnight cases handled.
Questions people ask
The things that come up about event duration calculators, answered plainly.
What time does my event end?
Enter the start and the length. A 90-minute event starting at 23:00 ends at 00:30 the next day, and the page says so rather than showing a bare 00:30.
How long should a meeting be?
Outside this tool's remit, but the arithmetic is here: an hour of six people's time is six hours of salary, which the page will price if you give it a rate.
Related tools
Recurring dates, time slots, rotations and calendar files.
Time Difference CalculatorTwo clock times or two full timestamps, and the difference in hours, minutes and seconds — including the overnight case, where the end time is smaller than the start.
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Calendar Event GeneratorTitle, time, location, a reminder and an optional recurrence — out comes a valid .ics file to download, plus a Google Calendar link for people who will not.
Duration CalculatorA duration in every unit from nanoseconds to decades, with the approximate ones flagged as approximate — because a month has no fixed length and any tool that pretends otherwise is guessing.