Measure complete calendar months and the leftover days between two dates.
Complete months use calendar arithmetic, so month lengths and month-end dates are handled correctly.
The calculator counts how many whole calendar-month moves fit between the earlier and later date. It then reports the remaining calendar days after those complete months.
The main answer uses complete calendar months plus remaining days. The decimal-month figure is an approximation based on the average Gregorian month length of 30.436875 days.
Because calendar months are not all 30 days long. Complete-month counting follows actual calendar boundaries.
The calculation uses clamped calendar arithmetic, so dates such as January 31 move safely into shorter months.
No. The calculator reports the absolute span and lets you swap the dates instantly.