This template uses Lua :
This template returns the number of weeks that have elapsed between two dates. If the second set of parameters is not included it will automatically calculate the days between a given date and today.
Each date can be entered in a single parameter, or each date can be entered as three parameters: year, month, day.
{{age in weeks|month1=6|day1=14|year1=1946|month2=8|day2=19|year2=1946}}
→ 9
{{age in weeks|1946|6|14|1946|8|19}}
→ 9
{{age in weeks|1946-6-14|1946-8-19}}
→ 9
{{age in weeks|14 June 1946|Aug 19, 1946}}
→ 9
{{age in weeks|month1=11|day1=07|year1=2012}}
→ 627
{{age in weeks|7 November 2012}}
→ 627
An error is shown if an entered date is not valid (1900 was not a leap year).
{{age in weeks|31 January 1899|29 February 1900}}
→ Error: Second date should be year, month, day
Birth, death and age templates
birth, death, age
Combined BDA template Description / use {{BirthDeathAge }} Combines functions of {{Birth date}}, {{birth-date}}, {{birth date and age}}, {{birth year and age}}, {{death date}}, {{death-date}}, {{death date and age}}, and {{death year and age}}.
Birth templates Description / use {{Birth date }} To display a birth date and related hidden metadata. {{Birth-date }} {{Birth date and age }} {{Birth date}} with suffix '(age N )'.{{Birth date and age2 }} {{Birth date and age}} plus age as of a specified date.{{Birth-date and age }} As {{Birth date and age}} , but accepts dates in text form ('15 June 1950', 'June 15, 1950', 'June 1950', etc.). {{Birth year and age }} Year of birth and approximate age. {{Birth based on age as of date }} To display approximate birth year and current age given a particular date (e.g. when a dated reference mentions the age of a person), only works for living people. {{Birth based on age at death }} To display approximate birth year based on age at death, or on age at a specific date if death date isn't known.
Death templates Description / use {{Death date }} To display a death date and related hidden metadata. {{Death-date }} {{Death date and age }} {{Death date}} with suffix '(aged N )'; also called with {{event date and age}} .{{Death-date and age }} As {{Death date and age}} , but accepts dates in text form ('15 June 1950', 'June 15, 1950', 'June 1950', etc.). {{Death date and given age }} To display a death date and specified age. {{Death year and age }} To display a year of, and approximate age at death.
age only
Reverse-determined age template Description / use {{Age }} Age based on number of complete years between two dates. {{Age nts }} {{Age}} with output formatted for use in number sortable tables .{{Age as of date }} Current age (in years) from a known age at a specified date. {{Age for infant }} Current age for infant: months and days up to one year, years and months up to three years, and years beyond age 3.