Born on 29 February — now what?
29 February exists only in leap years, so usually only every four years. Anyone born on that day strictly speaking only has a "real" birthday every four years. In English these people are affectionately called "leaplings". It is simply a special date of birth — with a few quirks worth knowing.
As a leap-day child you can also calculate your age perfectly correctly in the <a href="/en/age-calculator">Age Calculator</a>: it counts the full years, months and days exactly and accounts for leap years automatically.
Why leap days exist at all
An Earth year — the time it takes the Earth to orbit the Sun once — does not last exactly 365 days, but around 365.2422 days. If this remainder were ignored, the seasons would gradually drift against the calendar. That is why the Gregorian calendar inserts an extra day every four years: 29 February. It is fine-tuned by an additional rule — full century years are only leap years if they are divisible by 400. The year 2000 was therefore a leap year, while 1900 was not.
When is the birthday celebrated in common years?
In the three years between two leap years, 29 February is missing from the calendar. The birthday is then celebrated either on 28 February or on 1 March — both are common and a matter of taste. Those who want to keep the link to February celebrate on the 28th; those who like the idea of being born "just after 28 February" choose 1 March.
Legally the question is handled pragmatically in many countries: for deadlines and age limits, a person born on 29 February is generally considered a day older at the end of 28 February in common years. Coming of age or similar age thresholds are therefore not postponed until 1 March.
How the age is calculated
For the pure age calculation the leap day plays no special role: the calculator determines the calendar difference between the date of birth and the reference date in full years, months and days. A person born on 29 February is simply one year older on each 28 February or 1 March of the following years — depending on how you count the missing day. The number of days lived rises by exactly one every day anyway, regardless of the calendar trick.
A nice detail: anyone looking at their days lived sees the leap days counted indirectly — over 40 years they add up to around ten extra days. How many it is for you is shown by the <a href="/en/age-calculator">Age Calculator</a>.
Conclusion
A birthday on 29 February is a rarity, but not a problem: in common years it is celebrated on 28 February or 1 March, and legally the end of 28 February counts. Your exact age — leap day or not — is calculated reliably in the <a href="/en/age-calculator">Age Calculator</a>.