Normalized Date Formats
The Date Authority Service normalizes dates into a standard form that is similar to the date format of the GEDCOM standard.
Date Formats
Date (optional Day and Month)
<Day> <Month> <Year>
Full-Date (optional BC)
Date [BC]
Range-Date
FROM <Full-Date> TO <Full-Date>
Alt-Date
<Full-Date> / <Full-Date>
Modified-Date
<Modifier> <Full-Date>
Modifier
before, about, estimated, calculated, after, stillborn
Day (Requires Month and Year)
1-31
Month (Requires Year)
January, Februrary, March, April, May, June, July, August, September, October, November, December
Year
0000-2008
Examples:
Day, Month & Year => Normalized
about 24 July 1801 => about 24 July 1801
aft 24 July 1801 => after 24 July 1801
bef 24 July 1801 => before 24 July 1801
calculate 24 July 1801 => calculated 24 July 1801
estimated 24 July 1801 => estimated 24 July 1801
Month and Year
abt July 1801 => about July 1801
aft July 1801 => after July 1801
bef July 1801 => before July 1801
calculated July 1801 => calculated July 1801
estimated July 1801 => estimated July 1801
Year
abt 1801 => about 1801
aft 1801 => after 1801
bef 1801 => before 1801
calc 1801 => calculated 1801
estimated 1801 => estimated 1801
Dual Dates- Single Day, Single Month & Double Years
about 24 July 1801-1802 => FROM 24 July 1801 TO 1802
aft 24 July 1801-1802 => FROM 24 July 1801 TO 1802
bef 24 July 1801-1802 => FROM 24 July 1801 TO 1802
calc 24 July 1801-1802 => FROM 24 July 1801 TO 1802
estimated 24 July 1801-1802 => FROM 24 July 1801 TO 1802
Dual Dates- Single Month & Double Years
abt July 1801-1802 => FROM July 1801 TO 1802
aft July 1801-1802 => FROM July 1801 TO 1802
bef July 1801-1802 => FROM July 1801 TO 1802
cal July 1801-1802 => FROM July 1801 TO 1802
est July 1801-1802 => FROM July 1801 TO 1802
July 1801- June 1802 => FROM July 1801 TO June 1802
Dual Dates-Double Years
abt 1801-1802 => FROM 1801 TO 1802
aft 1801-1802 => FROM 1801 TO 1802
bef 1801-1802 => FROM 1801 TO 1802
cal 1801-1802 => FROM 1801 TO 1802
est 1801-1802 => FROM 1801 TO 1802
Alternate Dates
1 Jul 1801 or 20 Jun 1802 => 1 July 1801 / 20 June 1802
Jul 1801 or Jun 1802 => July 1801 / June 1802
BC Dates
bc 180 => 0180 BC
3000 bc => 3000 BC
AD Dates
ad 180 => 180