Months Between Dates Calculator
Count whole calendar months between two dates, with the leftover days reported separately.
Result
Months between
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How to use this calculator
- Enter the start and end date. Order does not matter.
- The whole-months number is "fully completed months". The hint shows the leftover days, plus a decimal-months estimate using the Gregorian average month length.
About this calculator
Months are tricky — they are not a fixed length, and "one month after January 31" could reasonably be either February 28 or March 3. This calculator follows the calendar-aware convention used by date-arithmetic libraries: a whole month is counted when you have reached or passed the same day-of-month in a later month. The leftover is reported as days.
Frequently asked
When the end date reaches or passes the same day-of-month as the start date. From Jan 15 to Feb 14 is 0 whole months (we have not reached the 15th). From Jan 15 to Feb 15 is 1 whole month.
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