Age Calculator
Calculate exact age in years, months and days from a date of birth.
Leave the second date blank to calculate age as of today.
Enter date of birth
How the Age Calculator Works
The calculator compares the Date of Birth with either today or the selected “Age as of” date. It uses calendar years, months and days rather than estimating every month as a fixed number of days.
Understanding the Results
Age in years, months and days
Shows age as completed calendar years and months plus the remaining days.
Completed years
The number of full birth years completed by the selected date.
Total days
The number of elapsed calendar days between the birth date and target date. If the start and target dates are the same, Total Days is 0.
Next birthday
The birthday date on or after the selected date. If the selected date is the birthday, it may show that same day.
Days until next birthday
The calendar days remaining from the selected date until the next birthday. It is 0 when the birthday is on that date.
February 29 Birthdays
For a February 29 birth, this calculator treats February 28 as the birthday in a non-leap year. This is a Worklity calculator convention, not a universal legal rule. For official or legal age requirements, verify the applicable rule and official records.
Practical Uses
Use the calculator to check age on a particular date, prepare school or application age calculations, complete forms, or make general personal date calculations. The result does not by itself establish compliance with official or legal age requirements.
Frequently Asked Questions
How is age calculated?
Age is calculated as completed calendar years and months plus the remaining days between the two dates.
Can I calculate my age on a past or future date?
Yes. Select any valid “Age as of” date that is the same as or later than the Date of Birth.
What happens for a February 29 birthday in a non-leap year?
For this calculator, February 28 is treated as the birthday in that year.
What does Total Days mean?
It is the number of complete calendar days elapsed from the birth date to the target date.
Why can't “Age as of” be earlier than Date of Birth?
Age is not defined before the birth date, so the calculator rejects an earlier target date.
Can I use this result as official proof of age?
No. The result is informational. Official requirements should use accepted documents, official records, and the applicable rules.