How the age is counted
Whole years first, then whole months, then the days left over — the same way a birthday is counted. So someone born on 31 January is one month old on 28 February (or 29 in a leap year), not "31 days" old.
Common questions
Why does 31 January to 28 February count as one month, not 31 days?
The calculator counts age the way people actually say it — in whole years, then whole months, then leftover days, the same logic a birthday uses. A calendar month has no fixed day-count, so "one month" is the correct answer even though February is short.
What's the oldest birth date it accepts?
120 years back from today. Anything older is rejected as out of range, along with dates that don't exist (like 31 February) or fall in the future.
Does it account for leap years?
Yes — the day/month arithmetic uses the real calendar, so leap-year Februaries and the extra day work out automatically, not as a separate rule.
For general information only — not medical advice. Talk to a doctor about anything that concerns you.