How the duration is calculated
The calculator uses the earlier of the two dates as the start and the later date as the end. It counts completed years first, then months, then days, borrowing from the previous month and year when needed. Because it uses the real length of each month, including 29 days in February during leap years, the duration is accurate across month-end and leap-year boundaries. The total days figure is the plain calendar-day difference between the two dates.
Frequently asked questions
How do I calculate the duration between two dates?
Subtract the earlier date from the later date. This tool breaks the result into completed years, months, and days, and also reports the total number of days.
Does the calculator count leap years?
Yes. It uses the real length of each month, including 29 days in February during leap years.
Does the result include both the start and end dates?
The total days figure is the number of days between the two dates. To count both endpoints inclusively, add one day.
What if I enter the later date first?
The calculator automatically uses the earlier date as the start, so input order does not change the result.
Are my dates stored anywhere?
No. All calculations run entirely in your browser. Nothing you enter is uploaded or saved on a server.
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Disclaimer: This calculator is provided for general informational purposes only. Results depend on the dates you enter and your device's calendar settings.