How many days are there between two dates
Pick the start and end dates and the calculator gives you, all at once, the total days, the breakdown in years, months and days, full weeks, hours and the business days (Monday to Friday). By default the end day isn't counted; switch it on if you need both ends included. For example, from 1 January to 31 December 2026 there are 364 days, or 365 if you include the last one.
Adding or subtracting time from a date
In the “Add or subtract time” tab, enter a date and an amount of days, weeks, months or years. It's useful for due dates, delivery deadlines, the end of a warranty or the date of an application: 90 days after 22 October 2026 is 20 January 2027. When adding months, if the day doesn't exist in the target month (for example, 31 January plus one month) the last day of that month is used.
What isn't counted
- Business days only exclude Saturdays and Sundays: public holidays are not subtracted, since they vary by country and region.
- Dates are calculated in whole calendar days, with no time zones or hours.
For an exact age use Age Calculator; for ratios and percentages, Percentage Calculator.
Frequently Asked Questions
How do I calculate the days between two dates?
Enter the start and end dates. The tool subtracts them and shows the total days, weeks, months and years.
Are the first and last days counted?
By default the start day is counted but not the end day. Tick “Also count the end day” to include both.
Do business days exclude holidays?
No: they only exclude Saturdays and Sundays. Holidays depend on each country and region, so you'd subtract them separately.
What happens when I add a month to the 31st?
If the target month is shorter, its last day is used: 31 January plus one month gives 28 or 29 February.