Calculate the duration and business days between two dates
Pick two dates and times to get the duration between them — broken down into days, hours, minutes, and seconds, plus a business-day count. Everything runs in your browser.
Measuring a life rather than an interval? The age calculator counts in calendar years, months, and days, and handles birthdays on the 31st and February 29. Adding up a week of shifts instead? The time card calculator totals clock-in and clock-out times with breaks, overnight shifts, and overtime.
7d
The headline is the gap written as days, hours, minutes, and seconds, with zero parts left
out, so a gap of exactly two weeks reads 14d and a gap of 90 minutes reads
1h 30m. Days are the largest unit. A three-month gap shows as something like
92d, never as months.
The five boxes underneath are the same gap converted into a single unit, each rounded down to a whole number. A gap of 14 days and 8.5 hours shows Total days as 14, not 14.35. If you need the fraction, divide Total hours by 24.
A project starts on Friday, October 23, 2026 at 09:00 and has to be done by Friday, November 6, 2026 at 17:30. With the browser set to UTC (or any zone that has no clock change in that window), the calculator shows:
Run the same two dates on a computer set to New York time and the result becomes 14d 9h 30m (345 total hours). US clocks fall back one hour on November 1, 2026, so an extra real hour passes between the two wall-clock times. Most of Europe changed its clocks a week earlier, on October 25, so a computer in London gets the extra hour too. This is correct for elapsed time: if you are billing by the hour or timing a process, the clock really did run for 345 hours. If you only care about calendar days, look at Total days, which is 14 either way.
The tool steps through the calendar one date at a time, starting on the From date and stopping before the To date, and counts every date that is a Monday to Friday. The time of day does not add part-days to this count. In the example above, that is Friday the 23rd, the full week of the 26th, and Monday to Thursday of the week of November 2nd: 1 + 5 + 4 = 10.
Two limits are worth knowing. There is no holiday calendar, so Thanksgiving or a bank holiday counts as a working day. And the dates are taken from the UTC calendar, not your local one. If your times are late in the evening in the Americas, or early in the morning in Asia or Australia, the UTC date can be a day ahead or behind your local date, and the count can be off by one. Midday times give the cleanest result.
Everything is computed with plain JavaScript dates in your browser. Nothing is sent anywhere, and once the page has loaded it keeps working offline. If your dates start out as Unix timestamps, convert them with the timestamp converter first. For the background on why seconds-since-1970 makes subtraction easy but months hard, see Unix timestamps and epoch time explained.
Because the period crosses a daylight saving change. The calculator measures real elapsed time between two instants, and both inputs are read in your browser's local time zone. In New York, midnight on October 31, 2026 to midnight on November 2, 2026 is 2d 1h, because clocks fall back on November 1 and that Sunday lasts 25 hours. In a zone without DST, the same dates give exactly 2d.
It includes the start date and stops before the end date. Friday, October 23 to Friday, November 6, 2026 counts 10 business days: the 23rd, then two full Monday-to-Friday weeks minus the final Friday. If you want both ends counted, set the To date one day later.
No. A business day here is any Monday through Friday. The tool has no holiday calendar, so subtract your local public holidays yourself.
Not from this tool. Months have different lengths, so a month is not a fixed number of seconds, and this calculator only works in fixed units (days, hours, minutes, seconds). For calendar years, months, and days, use the age calculator, which accepts any two dates, not only birthdays.
You get the same size of gap, with a note underneath that says To is before From. The totals and the business-day count are always shown as positive numbers.
No. Both fields are standard datetime-local inputs, read in the time zone your device is set to. To compare a time in Tokyo with one in London, convert one of them first with the time zone converter.
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