The exact distance between two moments in time
Date arithmetic goes wrong in different timezones and around daylight saving boundaries. This calculator works in explicit timezones, counts working days and shows you the components of the difference rather than a single rounded number.
- Zones
- Explicit timezones
- Working days
- Counted
- Output
- Full breakdown
| Unit | Value |
|---|
How to use it
- Set both dates Pick the start and the end date and time. Each side has its own timezone, so a handoff between two offices is measured correctly.
- Read the breakdown The result is given in days, hours, minutes and seconds, plus weeks, months, working days and a percentage of a year.
- Check the calendar view A month grid highlights the range and marks the weekends and public holidays in your selected country.
Questions people ask
How are working days calculated?
Monday to Friday, excluding weekends and the public holidays registered for the selected country and year. If you need a different working week, count the calendar days and subtract manually.
Is the end date included?
The difference is the number of whole days between the two moments. For an inclusive count of days touched, add one, which is the convention in project planning tools.
How are months calculated?
As whole calendar months, with the leftover days counted separately. This is why 30 days is not one month in this calculation, and why a licence described in months behaves differently from one described in days.
Does it account for daylight saving?
Yes. The hours are derived from the actual timestamps, so a day that is 23 or 25 hours long is counted correctly. The two timezones are explicit so you can see which rules applied.
Can I add a duration to a date?
The second field accepts a date, and the difference is computed between them. To add a number of days, set the end date to the start date plus that offset, and the breakdown shows the components.
Which public holidays are included?
The major national holidays for the selected country and year, with fixed and observed dates handled. Regional and company holidays are not included, because there is no authoritative source for them.
Reference
Working out what a deadline means
| Measure | Value |
|---|---|
| Total calendar days | `45` |
| Working days (Mon–Fri) | `31` |
| Full weeks | `6 weeks and 3 days` |
| In hours | `1,080 hours` |
Details that catch people out
On a spring-forward date the day is 23 hours long and on an autumn day it is 25. Any calculation that assumes 24 hours per day is wrong twice a year, which is why the hours component here is computed from real timestamps rather than from a day count.
Guides that go deeper
- UTC vs Local Time: The Bugs It Causes 6 min read · Why storing local time is a bug waiting to happen, how daylight saving breaks naive date…
Last reviewed 2026-10-02. Every tool on DevSnap runs entirely in your browser, so whatever you paste here never reaches a server.