About the Age Calculator
Enter a date of birth and an optional comparison date. The calculator returns completed age in calendar years, months, and days.
Important Note
Calendar months have different lengths, so age should be calculated using calendar dates rather than an average number of days.
Calculation Standards
This tool uses documented formulas and high-precision internal values. Displayed results may be rounded for readability. Review the assumptions and verify important decisions with a qualified professional.
Read our calculation methodology