You have spent months building a family tree in one program. Now you want to move it somewhere else. Or a cousin has emailed you a file with a .ged extension and you have no idea what to do with it.
In both cases, the answer is GEDCOM.
What GEDCOM is
GEDCOM stands for Genealogical Data Communication. It is a standard file format for exchanging family tree data between different genealogy programs.
The Church of Jesus Christ of Latter-day Saints created the first version in 1984. The goal was simple: let researchers move their data between software without losing it. Before GEDCOM, switching tools meant starting over.
Think of it like a universal translator. Ancestry, MyHeritage, Gramps, Family Tree Maker, and dozens of other programs all speak different internal languages. GEDCOM is the shared format they all understand. You export from one, import into another, and your tree comes along.
What a GEDCOM file contains
A GEDCOM file is plain text. You can open one in any text editor and read it. The format uses numbered levels and tags to describe people, families, events, sources, and notes.
Here is what a few lines look like:
0 @I1@ INDI
1 NAME Jan /Kowalski/
1 BIRT
2 DATE 12 MAY 1892
2 PLAC Krakow, Poland
That block describes an individual (INDI) named Jan Kowalski, born on 12 May 1892 in Krakow, Poland. The numbers on the left indicate nesting. Level 0 is the record itself. Level 1 holds the record's properties. Level 2 holds details of those properties.
A typical GEDCOM file contains:
- Individuals - names, birth dates, death dates, places, occupations, and other personal facts.
- Families - who married whom, who their children were, and when those events happened.
- Sources - where the information came from. A census record, a parish register, a family Bible.
- Notes - free-text annotations attached to people, events, or sources.
The structure is hierarchical but not complicated. Every genealogy program that reads GEDCOM knows how to turn those tagged lines back into a visual family tree.
GEDCOM 5.5.1 vs GEDCOM 7
There are two versions of the standard you will encounter in practice.
GEDCOM 5.5.1 was released in 1999. It is still what most genealogy software exports by default. If someone sends you a .ged file today, it is almost certainly 5.5.1. The format works, but it shows its age. Character encoding is inconsistent. Multimedia support is minimal. The specification left room for interpretation, so different programs sometimes export the same data in slightly different ways.
GEDCOM 7 arrived in 2021. It modernizes the format with proper Unicode support, better multimedia handling, clearer extensibility rules, and more inclusive relationship structures. The specification is tighter, which means fewer surprises when moving files between programs.
Adoption of GEDCOM 7 is growing but still uneven. Some major platforms support it. Others are still catching up. For maximum compatibility today, 5.5.1 remains the safer choice. But GEDCOM 7 is where the standard is headed.
Why GEDCOM matters
GEDCOM matters because of one principle: your research should not be locked into any single platform.
Genealogy software comes and goes. Companies get acquired, products get discontinued, free tiers get removed. If your family tree exists only inside one service with no way to export it, you are one business decision away from losing access to years of work.
GEDCOM is your escape hatch. As long as a program can export to GEDCOM, you can take your tree and move it. That portability is not a nice-to-have. It is a basic requirement for any serious research workflow.
This also works in the other direction. When you find a relative who has been researching the same family for decades, they can share their tree as a GEDCOM file. You can import it into whatever tool you prefer, review what they have found, and build on it.
Where GEDCOM falls short
GEDCOM is good at what it was designed for: people and relationships. But it has real limitations.
Source citations vary wildly. The standard defines a structure for sources, but every program fills it differently. An export from Ancestry and an export from Gramps encode the same source citation in incompatible ways. When you import, the citations arrive but may need cleanup.
Multimedia is referenced, not embedded. A GEDCOM file can point to an image file (1 FILE photo.jpg), but the image itself is not inside the GEDCOM. If you share the .ged without the associated image files, the references break.
Non-Western names are awkward. The format assumes a given-name-plus-surname structure. Names that do not follow that pattern - patronymics, mononyms, names in non-Latin scripts - are harder to represent accurately, especially in 5.5.1.
Relationship types were limited. GEDCOM 5.5.1 was built around a husband-wife family model. Same-sex relationships, non-marital partnerships, and other family structures did not have clean representations. GEDCOM 7 improved this with more flexible relationship tags, but older files do not benefit.
None of these limitations make GEDCOM useless. They mean you should expect some friction when moving data between programs. A clean export from one tool is rarely a perfect import into another.
Practical tips for importing and exporting
If you are about to move a tree via GEDCOM, keep these things in mind.
Always review the import. Do not import a GEDCOM file and assume everything transferred perfectly. Check a handful of people, especially those with complex source citations or non-Latin characters. Look for missing dates, garbled names, and orphaned source references.
Some programs export cleaner GEDCOM than others. If you have a choice of where to export from, test a small file first. Export, import into the destination, and compare. Programs that stick closely to the specification produce files that other programs handle better.
Keep both versions. When you import a GEDCOM file, save the original .ged file somewhere safe. If the import loses something, you still have the source.
Watch the file size. A tree with tens of thousands of people produces a large GEDCOM file. Most programs handle this fine, but the import may take a few minutes.
KleioBase supports GEDCOM import and preserves the full data structure from the file - people, families, events, sources, and notes all come through. You can review a preview of what the file contains before committing to the import, so there are no surprises.
The future of GEDCOM
GEDCOM 7 is the clearest sign that the genealogy community takes data portability seriously. The standard is maintained by an open committee (GEDCOM Steering Committee under FamilySearch), the specification is public, and feedback from software developers shapes each revision.
The broader question is whether GEDCOM will remain the only interchange format or whether alternatives will emerge. Some developers have experimented with JSON-based and linked-data approaches. None have gained the adoption that GEDCOM has. For now, GEDCOM is the standard, and GEDCOM 7 is a meaningful improvement on it.
What matters most is the principle behind the format. Your genealogical research is yours. You should be able to take it with you, share it with relatives, back it up, and move it between tools without losing what you have built. GEDCOM, for all its quirks, makes that possible.
Start building your family history
Upload a record and let KleioBase transcribe, translate, and connect it - all in one place, with a research partner that remembers everything you find.
Join the waitlist