Sooner or later, every family historian meets the same four letters: GEDCOM. It is the file your family tree lives in whenever it travels from one program to another. Understand it once and you will never feel trapped by a genealogy website again, because GEDCOM is the thing that lets you pick up your entire tree and carry it somewhere better. This guide walks through all of it: what the file is, how it is built, how to get one out of the big sites, and how to open it.
What a GEDCOM file is
GEDCOM, with the file extension .ged, is the common language of genealogy. It is a plain-text file that holds everything in a family tree: each person, their dates and places of birth, marriage and death, how they connect to one another, and the notes you have written about them. Almost every genealogy program ever made can read and write it, which is exactly why it matters. Your tree is only truly yours if you can move it, and GEDCOM is how it moves.
The name stands for Genealogical Data Communication. It was created in the 1980s by the Family History Department of The Church of Jesus Christ of Latter-day Saints, the same people behind FamilySearch, so that the dozens of competing genealogy programs could trade data instead of locking it away. Four decades later it is still the standard, and that longevity is the point. A format that everyone speaks is a format no single company can take away from you.
What is inside one
Open a GEDCOM in a text editor and you will see a tidy list of lines, each beginning with a number. Those numbers show how the information nests. People are stored as individual records, couples and their children as family records, and the two are tied together by simple cross-references. Dates, places, occupations and notes hang off each person. It looks technical at first glance, but the underlying idea is plain: a list of people, a list of families, and the links between them. We pull the format apart line by line in The GEDCOM File Format Explained.
The versions: 5.5.1 and 7.0
You may see two version numbers. GEDCOM 5.5.1, finalised in 1999, is the version almost every program still exports and reads. It is the safe, universal choice, and if you are unsure which to use, use this one. GEDCOM 7.0, released in 2021, is a modern update that handles photos, languages and modern dates more cleanly, but support is still spreading. For moving a tree today, 5.5.1 will work everywhere. A good importer reads both, so you rarely have to think about it.
How to get a GEDCOM out of the big sites
Every reputable service lets you export one, though they sometimes bury the button. The short version:
- Ancestry: open your tree, go to Tree Settings, and choose Export tree. We cover this in detail in How to Export a GEDCOM from Ancestry.
- MyHeritage: Family tree, then Manage trees, then Export to GEDCOM.
- FamilySearch: a little different, since FamilySearch is one shared tree; tools like the FamilySearch GEDCOM export or a third-party helper can pull your branch.
One honest warning that catches everyone out: a GEDCOM carries the tree data, not the photographs. The pictures you uploaded live separately and have to be downloaded on their own before a subscription lapses. Records and hints, which the big sites sell by subscription, do not travel either. What you get is the genealogy itself, every person, date, place, marriage and note, which is the part that is truly yours.
How to open a GEDCOM file
You do not need special software to look inside a GEDCOM; any text editor will show you the raw lines. But to actually see your family, you want a program that turns those lines back into a tree. Drop the file into Dynasty House and a two-thousand-person tree renders, fully pannable, in about five seconds, with every person, date, place and note intact. You can open your GEDCOM here, free, for up to a hundred people, and export it again any time.
Why GEDCOM is your insurance policy
The big sites would rather you forgot this file existed. It is the one format every program speaks, which makes it the one thing standing between your family history and a renewal fee. As long as you can produce a complete GEDCOM in a click, you are free: free to leave, free to back up, free to keep your tree somewhere it will outlive any single company. That is the whole reason we built Dynasty House around it. Import freely, export freely, and never get held hostage.
Learn the file once and the rest of genealogy gets easier. Your tree stops being something a website holds for you, and becomes something you hold yourself.