Date Difference Calculator
Count the days, weeks, months and years between two dates.
Difference
358 days
- Weeks and days
- 51 weeks, 1 day
- Years, months, days
- 0y 11m 24d
- Total months
- 11
How to use the Date Difference Calculator
- Choose the start date and the end date.
- Tick 'Include the end date' if both the first and last day should count.
- Read the total days, the weeks and days, and the years, months and days.
- Copy the summary if you need to paste it into a message or document.
About the Date Difference Calculator
How many days are there between two dates? This calculator finds the exact gap between a start date and an end date, and shows it as days, as weeks and days, and as years, months and days. It is useful for project deadlines, notice periods, trip planning, pregnancy and event countdowns, and contract terms.
The number of days is the difference between the two calendar dates, so 1 January to 25 December 2026 is 358 days. The tool uses whole calendar days, which avoids errors caused by clocks changing for daylight saving time.
Counting the end date adds one day. That matters for questions such as how many days a hotel stay covers or how long a leave period lasts, where both the first and last day are included. Weeks and days come from dividing the total by seven. The years, months and days figure counts complete months first and then the leftover days, so it follows the actual lengths of the months in between, including leap years. If the end date is earlier than the start date the two dates are swapped and a note tells you.
Frequently asked questions
Does the calculation include the end date?
Not by default. Tick the box to count the end date too. For two identical dates the answer is 0 days, or 1 day with the end date included.
Are leap years handled?
Yes. The tool uses the real calendar, so 28 February to 1 March spans two days in a leap year and one day otherwise.
What if my end date is before my start date?
The dates are swapped for you, and a message explains it. The size of the gap is the same either way.
Does it count working days?
No. It counts every calendar day, including weekends and public holidays.
Why does years, months and days differ from total months?
Total months counts only complete months. The days left over are shown separately in the years, months and days line.