Age in Months Calculator

About this calculator

This calculator shows completed calendar months since a selected birth date. It can help when an age needs to be expressed in months rather than years and days.

How it works

The calculator counts the difference in calendar months, then subtracts one if the current day of the month has not yet reached the birth day. Months are calendar units, so they do not all contain the same number of days.

Results use calendar dates in your device's local date context. Daylight-saving changes do not alter the calendar-day count. For legal, medical, financial or official purposes, confirm the relevant rules with the responsible organisation.

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