Calendar method
We count complete months from the earlier birth date, then the remaining days. Twelve months make one year. If a month is shorter, we use its last day. Total days use UTC dates to avoid daylight-saving changes.
Age gap calculator
Enter two birth dates to calculate the age difference.
For adults age 18 and older. Birth dates stay in this tab.
See the difference
Enter the two birth dates. You will see complete years, remaining months and days, and the total days.
Read the calendar methodExample
January 15, 1990 and March 20, 1995 are 5 years, 2 months, and 5 days apart. Reversing the dates changes which person is older, not the gap.
Common questions
Why can another calculator give a different result?
Months have different lengths. This tool counts January 31 to February 28 as one month. Other tools may use a different rule or divide total days by 365.
Are the birth dates saved?
No. They stay in this browser tab and are not added to the URL, browser storage, or custom analytics events.