Can I enter a Buddhist Era year?

Yes. Choose B.E. and type e.g. 2533; it is converted to 1990 C.E.

When does someone born on 29 February turn a year older?

In years without 29 February, we count it as 1 March, following the period rule in Civil and Commercial Code s.193/5.

Age in years, months and days, and days until your birthday

Verified + our stated conventionLast verified 25 September 2026

Date of birth

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Count whole years, then whole months, then the remaining days
If the final month has no matching day (e.g. 31 Feb), the period completes on the 1st of the next month

Civil and Commercial Code s.16: age is counted from the date of birth
Civil and Commercial Code s.193/5: if the final month has no corresponding day, the last day of that month ends the period
The 29 February case is our interpretation, not legal advice

Internal reference: reference/11_age.md

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