Days Between Dates Calculator
Pick two dates to get the exact difference in days, weeks, months and years. Turn on business days to count working days only, and add holidays to skip.
How to use the Days Between Dates Calculator
- Pick a start date and an end date. Use the Today buttons for a quick start; the order doesn't matter.
- Choose whether to include the end date. Turn it on when both the first and last day count, such as a holiday from Monday to Friday.
- Turn on business days to count only working days. Untick days that aren't working days and add any public holidays to skip.
- Read the result in days, plus weeks, months and years, and copy it with one click.
How the date difference is calculated
Both dates are treated as whole calendar days, so the result is the same in every time zone and never changes when clocks go forward or back. The number of days is simply the later date minus the earlier date. With Include end date ticked, one day is added so that both the first and the last day are counted.
| From | To | Days | Including end date |
|---|---|---|---|
| 1 Jan 2026 | 31 Dec 2026 | 364 | 365 |
| 1 Jan 2024 | 1 Jan 2025 | 366 (leap year) | 367 |
| Mon 5 Oct 2026 | Fri 9 Oct 2026 | 4 | 5 (all business days) |
| 15 Jan 2026 | 20 Mar 2026 | 64 (2 months, 5 days) | 65 |
Business days and working days
Business day mode counts only the days you mark as working days. Monday to Friday is the default, but you can choose any pattern, for example Sunday to Thursday or a six-day week. Paste your public holidays (one date per line, such as 2026-12-25) and any that fall on a working day are skipped. This is useful for delivery times, notice periods, project plans and invoice due dates.
Days, weeks, months and years
Days and weeks are exact. Months and years follow the calendar: the calculator counts whole months from the start date and then the leftover days, because months have 28 to 31 days. The "in years" value divides the days by 365.2425, the average length of a year in the Gregorian calendar.
Frequently asked questions
How do I count the days between two dates?
Subtract the earlier date from the later one. This calculator does it for you using calendar dates, so leap years and different month lengths are handled automatically.
Does the result include the end date?
By default no: from 1 January to 2 January is 1 day. Tick "Include end date" to count both the first and the last day, which adds 1 to the total.
How are business days counted?
Business days are the days you mark as working days (Monday to Friday by default) between the two dates, minus any holidays you list that fall on a working day.
How are months between dates calculated?
The calculator counts whole calendar months first and then the remaining days. For example, 15 January to 20 March is 2 months and 5 days.
Are time zones or daylight saving a problem?
No. Dates are compared as whole calendar days, so daylight saving changes never add or remove an hour from the result.
How many days are in a year?
A common year has 365 days and a leap year has 366. Leap years are divisible by 4, except century years that are not divisible by 400, so 2000 was a leap year but 1900 was not.