For years the answer was “you can't — use a third-party app.” That changed: FamilySearch now has an official export that saves your ancestors from the shared Family Tree as a GEDCOM file. Here's the new way, and the fuller old way.
Go to familysearch.org/innovate/export while signed in to your free FamilySearch account. This is FamilySearch Labs' official tree-export feature — if the address has moved, search FamilySearch for “export GEDCOM” to find its current home.
The tool walks your ancestor lines in the shared Family Tree — up to 8 generations starting from you — and packages them as a GEDCOM file in the modern GEDCOM 7 format.
When the export finishes, download it. Large ancestor sets can take a moment to generate; the result is a plain .ged file you can open anywhere.
The official export covers your ancestor lines, not cousins and descendants. For a fuller branch, use a FamilySearch-certified desktop program — RootsMagic, Ancestral Quest, or Legacy Family Tree — sign in to FamilySearch from inside it, download the branch you want into the program, then use its own File → Export GEDCOM.
Drop it into the free viewer to explore every person, chart, and place — or convert it straight to PDF, Excel, or a shareable web page. Everything runs in your browser; nothing is uploaded.
Open the viewerBrowse the toolsGEDCOM 7 is the 2021 revision of the standard, and FamilySearch (its steward) exports in it natively. Modern programs read it; the gedfile.com viewer and every tool on this site handle both 7.0 and the older 5.5.1. If a legacy desktop program refuses the file, open it here and use the converters — or read what actually changed in the format guide.