Work out the time between two dates in days, hours, and minutes, with calendar months, totals, and working days.
Start here Set the start date and time, then the end.
Both values are read in your own time zone, UTC.
Understand the format
There are two right answers to "how long between these dates", and mixing them up is where billing, SLA, and holiday calculations go wrong.
Ask how long from 31 January to 31 March and there are two defensible answers. A calendar says 59 days. A stopwatch says 58 days and 23 hours, because the clocks went forward an hour in between. Neither is a bug: one measures the wall calendar, the other measures physical time.
This page reports both, and tells you when they disagree. Which one you want depends on the question. Billing by the hour and measuring an SLA want elapsed time. Booking leave, counting notice periods, and working out an age want calendar days, because people count mornings, not seconds.
A month is between 28 and 31 days, and a year is 365 or 366. That makes "one month" meaningless as a duration in seconds: one month from 31 January is 28 February in most years, and adding thirty days gives 2 March instead. Any code that treats a month as 30 days will produce dates that drift.
The calendar breakdown here counts the way a person does, taking whole months first and then the remaining days. That is why it can report "2 months, 0 days" for a range whose elapsed time is not a round number of hours.
The working-day count here is whole Monday-to-Friday days in the range. It knows nothing about public holidays, which vary by country, region, and sometimes by employer, and nothing about a working week that runs Sunday to Thursday, as it does in much of the Middle East.
That is a deliberate limit rather than an oversight. A working-day figure is only meaningful against a stated calendar, so use this as a starting point and subtract the holidays that apply to the people involved.
Step by step
The calculation runs in your browser using the Date and Intl APIs. The dates you enter are not transmitted or stored.
Worked examples
Input
31 January 2026 00:00 to 31 March 2026 00:00, UK time
Result
Elapsed 58 days 23 hours; calendar 59 days
British clocks moved forward on 29 March, so one hour of the calendar never happened. Both figures are correct.
Input
17 August 2026 00:00 to 24 August 2026 00:00
Result
7 days elapsed, 7 calendar days, 5 working days
The working-day count skips the Saturday and Sunday, but knows nothing about bank holidays.
Reference
| Question | Use | Why |
|---|---|---|
| How much time actually passed? | Elapsed days and hours | Physical time, unaffected by clock changes. |
| How many days on the calendar? | Calendar days | Counts dates, so a clock change does not shorten a day. |
| How old is this? | Years, months, days | Matches how people state ages and anniversaries. |
| How long did the job run? | Total seconds or minutes | Precise and unit-free for machine comparison. |
| How many business days? | Working days | Weekdays only. Subtract public holidays yourself. |
Practical Guide
Troubleshooting
FAQ
Because the clocks changed inside the range. A day that loses an hour to daylight saving really is 23 hours long, so the elapsed count and the calendar count differ by that hour.
No. The working-day figure is weekdays only, because holidays vary by country, region, and employer. Subtract the ones that apply to you.
Your own, as reported by your browser. If the dates belong to another zone, convert them first with the Time Zone Converter.
The duration is reported with a note that it runs backwards, rather than silently showing a negative number or swapping the values without telling you.
By calendar. Whole months are taken first, then the remaining days, which is how people describe ages and notice periods.
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