Calculate age
Calculate completed calendar years, months and days between birth and a reference date.
Input & settings
How to use this tool
Enter both dates explicitly. The reference date must be on or after birth. A February 29 anniversary clamps to February 28 in a non-leap year.
Limits and behavior
Uses the Gregorian calendar for years 1900–2100. Dates must be exact YYYY-MM-DD values. Calendar days are counted at UTC midnight, independent of daylight saving. Age is decomposed by completed months anchored to the birth day, clamped to the last day of shorter months; remaining days follow that anchor. This is not a legal age determination. Input is limited to 1 MB and output to 3 MB. No input content is saved by CraftAI.
Find age in calendar years, months and days
Enter a valid date of birth and a reference date to see completed calendar years, remaining months and days.
Why does age differ from dividing elapsed days by 365?
Calendar years and months vary in length, including leap years, so calendar age is not simply total days divided by a constant.
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