Date Difference Calculator
Knowing the exact number of days, weeks, or months between two dates is useful in more situations than most people realize. Whether you are counting down to an event, calculating a deadline, figuring out how long a project took, or checking how many days until a contract expires, this free date difference calculator gives you the answer instantly.
How to use it: select a start date and an end date, then click Calculate Difference. The tool shows the total number of days, weeks, months, and years between the two dates, plus the exact breakdown in years, months, and days combined, and an approximate business days count.
The calculator automatically handles the order of the dates — if you accidentally put the later date first, it corrects itself. It also accounts for leap years and varying month lengths for maximum accuracy.
Common uses include calculating how many days until a birthday, wedding, or vacation, figuring out the duration of a work contract, measuring how long ago a past event occurred, counting days between invoice date and payment date, and planning project timelines.
This tool is completely free and works in your browser with no data sent to any server.
FAQ
Q: Does this calculator count the start date and end date?
A: The result counts the days between the two dates. If you want to include both the start and end day, add 1 to the total days shown.
Q: How are business days calculated?
A: The business days figure is an approximation based on 5 working days per 7-day week. It does not account for public holidays, which vary by country.
Q: Can I calculate dates in the past?
A: Yes. Enter any two dates — past, present, or future — and the calculator will find the difference between them.
Q: Does it handle leap years?
A: Yes. The calculator accounts for leap years automatically when computing the exact day count.
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