Time & Calendar
Basic

Age in Years

Whole years elapsed since a birth date.

Formula

A=⌊JDNtoday−JDNbirth365.2425⌋A = \left\lfloor \dfrac{JDN_{today} - JDN_{birth}}{365.2425} \right\rfloor

Variables

JDN_{today}Today
JDN_{birth}Birth date

Example

10,000 days old ⇒ about 27.4 years

Did You Know?

The mean Gregorian year is 365.2425 days — that fractional bit is exactly what leap years exist to absorb.

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