What it does
The Date Calculator works out the time between two dates (in years, months and days, total days, weeks, working days and weekend days) and adds or subtracts days, weeks, months and years from a date. Use it for deadlines, notice periods, project plans and contract terms.
How to use it
Difference between dates
- Enter the From date and the To date. Swap reverses them.
- Tick Include the end date (count both days) when both days should count, for example for leave or hotel nights inclusive of check-out.
- Read the total days, weeks, working days (Mon–Fri), weekend days, months, hours and minutes.
Add or subtract
- Enter the Start date.
- Choose Add or Subtract and enter years, months, weeks and days.
- Tick Count days as working days to skip Saturdays and Sundays, for deadlines given in working days.
- Read the resulting date, its weekday and how far it is from today.
Examples
| Question | Answer |
|---|---|
| 1 Jan 2026 to 31 Dec 2026 | 364 days, 260 working days (365 and 261 including the end date) |
| 28 Oct 2026 to 25 Dec 2026 | 58 days |
| 31 Jan 2026 + 1 month | 28 Feb 2026 |
| 21 Oct 2026 + 90 days | 19 Jan 2027 |
Good to know
- Working days count Monday to Friday. Public holidays are not taken off, because they differ by country and region.
- Adding a month to the 31st lands on the last day of a shorter month.
- By default the start date is not counted, which matches how most contracts and deadlines count days.
FAQ
How old is someone born on a given date? The Age Calculator gives the exact age and the next birthday.
How many weeks until a date? Enter today and the date; the result shows weeks and days.