Date Difference Calculator
Everything runs in your browser. Your data never leaves your device.
What this tool does
Pick two dates and the calculator tells you how far apart they are: the total number of days, the same gap in years, months and days, and the number of whole weeks plus extra days. It works for dates in the past, the future or a mix, so you can use it for deadlines, pregnancy and project timelines, contract periods, countdowns and anniversaries.
How to use it
- Choose the start date.
- Choose the end date. It starts as today.
- Read the total days and the breakdown beneath it.
How the calculation works
The total days figure is the exact number of calendar days between the two dates, including leap days. The years, months and days breakdown counts full months first, using the real length of each month, and then the remaining days.
Example: from 1 January 2024 to 15 March 2024 is 74 days, which is 2 months and 14 days, or 10 whole weeks and 4 extra days. From 1 January 2024 to 1 January 2025 is 366 days because 2024 is a leap year.
Notes
Dates use the Gregorian calendar and do not depend on time zones. The end date is not counted, which matches how most calendars and date functions measure the gap. If you need the age of a person instead, use the age calculator. Your dates are processed in your browser and are never uploaded.
Frequently asked questions
Are both the start and end dates counted?
No. The result is the number of days from the start date to the end date, so 1 January to 2 January is 1 day. Add 1 if you want to count both days inclusively.
Does the order of the dates matter?
No. If the start date is later than the end date the tool swaps them, so you always get a positive difference.
Are leap years included?
Yes. The total number of days uses real calendar days, so a full leap year such as 2024 counts as 366 days.
Does it exclude weekends or holidays?
No. It counts every calendar day. For working days, subtract weekends and public holidays yourself, or divide by 7 to see the number of full weeks.