GEDCOM is an acronym for Genealogical Data COMmunication. GEDCOM was developed
by the Church of Jesus Christ of Latter-day Saints. The current release is 5.5.
The GEDCOM format was created to help standardize the ability to export and import
files from one genealogy application into another. To understand how this is accomplished,
some terms need to be explained.
Standard Programming Terms Used for Storing Genealogy Data
Tags: are generally four (4) characters in length and are mostly
predefined. Custom tags can also be created. Tags allow a field to occur any number
of times within a record. Tags are set in a hierarchy that is used to capture and
store the data associated for people's names, events, sources, notes, media, etc.
The concept is similar to storing information in a spreadsheet.
Hierarchy: The beginning of a new logical record is designated
by a line whose level number is 0 (zero). Each new level number must be no higher
than the previous line plus 1.
Fields: Stores the data for each tag. The programmer defines
how many characters can be stored in a field.Records:
The field and tags that belong together are records.Computer Language:
is how a program reads and writes the characters (A-Z, numbers, etc.) stored on
a computer.
Screen Overview: Although you see "Given Name" as
part of the screen where you input your data, the tag that actually stores the information
is GIVN. Tags are created in a hierarchy so information stays together. SURN, GIVN,
and NICK are subsets of NAME. DATE and PLAC are subsets of birth and death.
Compatibility Issues Due to Tags
So the concept of following a standard seems simple enough and the data from one
program should transfer seamlessly to another, right? Well, that is not necessary
what happens. Programs do not all work the same and information may not be transferred
from one program into another.
There are many GEDCOM tags that are used to store genealogy information. A company
may decide that some tags are not important to them, so they exclude them.
Programmers can manipulate tags in three (3) ways. When importing a GEDCOM file
from one program to another they can write executable changes to tags where they
combine two tags into one upon importing the information into their program. They
can also change a tag name, or decide which sublevel belongs to which tag.
Custom tags can also be created which may not be readable in other programs. This
is mainly seen with source citation templates, and the extra information that they
store. Individual and marriage events are allowed to be custom as per the GEDCOM
standard, and most programs do read and write them. Below are the standard individual
events:
Programs Tested with Standard GEDCOM Programming
We tested several programs to show that not all programs import and export information
the same. As genealogists this may help you decide which program you would or would
not want to use. The test was conducted by creating a GEDCOM file with certain tags.
The file was imported into the new program, saved, and then exported as a GEDCOM.
Both files were then opened in notepad and compared what happened to the information
and the tags. The results below are to help genealogists understand that they may
lose family history data going from one application to another.
Screen Overview
Ok indicated the information transferred from the import and
export successfully. N/A indicates the information did not transfer properly. Shortened
indicates the field does not have enough space to accommodate the original text. Added indicates tags were added during the export process from
the imported program vs. the original data. See note indicates
further information about the tag was captured. Read the test results in the notes
section.
Notes for Each Tested Program
Ancestry.com Sources were not attached to events and did not
show up under the person's timeline. REPO: AUTH, PUBL, NOTE, and TEXT did not show
up anywhere in the program, but the information did import as it showed up in the
export with the caveat that the NOTE and TEXT was combined into 1 tag.
AgeLong Tree Converted @R to @S. Custom events did not import
or export.
Family Historian Converted @R to @S
FamilyTreeMaker Sources that are not attached to events for a
person are not shown in the family view. They are shown in the Source Group Tab.
Legacy Due to its Sourcing incompatibility, the file did not
import correctly. The person's name and information did not appear in the program,
but the file did read information and exported. The program added sentence structure
to Events adding unnecessary data.
MyHeritage Only has TITL, PAGE, and TEXT tags for sources. We
did not test the export feature, as it requires a subscription fee.
Reunion Combined SOUR tags: PAGE, TEXT, and NOTE to PAGE. Combined
REPO tags: NOTE and TEXT to TEXT
RootsMagic Combined parts of the original NAME, TITL tags. It
also combined SOUR Page and Text to 1 field. The program added standard events to
each person which added an extra 22k per person to the exported GEDCOM file. Sources
not added to events are not shown for the person.
The Master Genealogists Combined NOTE and TEXT into 1 field -
NOTE. Custom events were converted into notes and misc events.
Tribal Pages Source Titles imported, but they were not attached
to people or events. Program tags include: TITL, ABBR, AUTH, PUBL, TEXT, URL, TYPE,
but the only tag that exported was TITL. You can add custom events, but only birth,
marriage, and death events exported. The note added several lines of gibberish (ANSEL
coding is used).
GEDCOM Files and Sync Issues
Learn how genealogy programs work from a technical standpoint and why genealogy
programs do not always sync your data from one application to another.