All functions / Date & Time
DATEDIF
The difference between two dates in years, months or days.
Syntax
=DATEDIF(start_date, end_date, unit)
Arguments
start_date: The earlier date.end_date: The later date.unit: "Y" years, "M" months, "D" days, "YM" months ignoring years, "MD" days ignoring months, "YD" days ignoring years.
Example
=DATEDIF(B2, TODAY(), "Y") → Age in whole years