How is age calculated when the birth day hasn't occurred yet this month?

The calculator borrows days from the previous calendar month and a year from the month count when needed, the same way you'd count on a calendar — so results stay accurate across month-end edge cases like calculating from January 31st.

Can I calculate age as of a date other than today?

Yes — change the "age as of" field to any date on or after the date of birth, useful for figuring out how old someone was (or will be) on a specific date.

Does this account for leap years?

Yes, all calculations use actual calendar dates via JavaScript's Date object, so leap years are handled automatically with no extra input needed.

Is my date of birth sent anywhere?

No. All math runs locally in your browser — nothing is transmitted or stored.

AGE CALCULATOR

Exact age in years, months, and days. Nothing leaves your browser.

Date of birth

Age as of

Age

26y 7m 23d

Total months319

Total weeks1,390

Total days9,732

130 days until next birthday.

How to calculate age

1
Enter a date of birth.
2
Optionally change the "age as of" date — it defaults to today.
3
Read the exact age in years, months, and days, plus totals and days to the next birthday.

Questions

How is age calculated when the birth day hasn't occurred yet this month?: The calculator borrows days from the previous calendar month and a year from the month count when needed, the same way you'd count on a calendar — so results stay accurate across month-end edge cases like calculating from January 31st.
Can I calculate age as of a date other than today?: Yes — change the "age as of" field to any date on or after the date of birth, useful for figuring out how old someone was (or will be) on a specific date.
Does this account for leap years?: Yes, all calculations use actual calendar dates via JavaScript's Date object, so leap years are handled automatically with no extra input needed.
Is my date of birth sent anywhere?: No. All math runs locally in your browser — nothing is transmitted or stored.