GEDCOM Format Reference
A plain-language reference for how the GEDCOM file format actually works: versions 5.5.1 and 7.0, character encoding, the structure of a line, and the tags.
GEDCOM is a plain-text format, which means you can open any .ged file in a text editor and read it. That is genuinely useful when something has gone wrong, and it is why this section explains the format rather than hiding it: almost every upload or transfer problem becomes obvious once you can read the three or four lines that describe it.
The structure is simple and completely uniform. Every line is a level number, an optional record ID, a tag, and a value — 1 BIRT, 2 DATE 4 JUL 1826 — with the level number expressing nesting instead of indentation. Understanding that one line format is enough to follow what your genealogy software actually exported, and to spot the point where a file was truncated mid-download.
Two versions matter in practice. GEDCOM 5.5.1 dates from 1999 and remains the interchange default that virtually every program can read and write. GEDCOM 7.0 was finalised in 2021 and fixes real problems — Unicode by default, structured citations, and GEDZIP, a container that finally bundles photos with the data instead of leaving them behind as broken file paths — but adoption has been uneven, and several programs support importing it before they support exporting it. The guides here cover both, along with the date qualifiers (ABT, BEF, AFT, BET…AND, CAL, EST) that encode how certain a date actually is, and the ANSEL character set that garbles accented names when it is read as anything else.
Start hereGEDCOM ViewerOpen a file and search it by name, then walk a person's parents, siblings, spouses, and children. Useful for confirming what your export actually contains before you take anyone's word for it.7 guides in this section
- A Genealogist's Glossary: GEDCOM Terms Without the JargonPlain-language definitions for GEDCOM terms like FAMC, ANSEL, dangling reference, and GEDZIP — for anyone who wants a translation, not a spec document.
- ANSEL Encoding Explained: Why Old GEDCOM Files Show Strange AccentsANSEL is the character encoding behind most pre-Unicode GEDCOM garbling. Here's what it actually is, why genealogy software used it, and how to spot it.
- Does My Genealogy Software Support GEDCOM 7.0?A sourced, dated look at which major genealogy platforms support GEDCOM 7.0 as of mid-2026 — and which are still 5.5.1-only, per FamilySearch's own tracker.
- GEDCOM 5.5.1 vs. 7.0: What Actually ChangedGEDCOM 7.0 changed Unicode handling, citations, and media bundling from 5.5.1. Here's exactly what's different and why it affects uploads and software support.
- How GEDCOM Dates Work: ABT, BEF, AFT, and Other Qualifiers ExplainedGEDCOM dates like 'ABT 1850' or 'BET 1900 AND 1905' follow a fixed set of qualifiers for uncertainty. Here's exactly what each one means and how to read them.
- Understanding GEDCOM's Level/Tag/Value Structure (for Non-Technical Users)Every line in a GEDCOM file follows one pattern: level, tag, value. Once you can read that pattern, error messages and file problems stop being a mystery.
- What Is GEDZIP, and Why Does It Matter for Photos?GEDZIP bundles your GEDCOM data and its photos into a single file, fixing the classic 'photos went missing' problem. Here's exactly how the format works.