How age is calculated
The calculator moves through complete years first, then complete months, then the remaining days. This keeps the result aligned with calendar dates.
Age—
Enter your details to calculate.
Age calculator guide
Use the date fields to calculate an exact age between a date of birth and any comparison date. The result is shown in years, months and days rather than as an approximate decimal age.
Useful for milestones
You can use the comparison date for birthdays, eligibility dates, anniversaries or any other date where an exact age matters.
Date order matters
If the comparison date is earlier than the date of birth, there is no valid age to calculate.
Frequently asked questions
Can I calculate age on a past date?
Yes. Choose any comparison date after the date of birth to see the exact age on that day.
Why is age not just days divided by 365?
Calendar years and months have different lengths, so dividing days by 365 only gives an approximation.
Does the calculator account for leap years?
Yes. Because it works with actual calendar dates, leap years are naturally included.
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