Local-first GEDCOM tools
Why your GEDCOM upload keeps failing — and how to fix it.
Large family trees fail to upload to FamilySearch for specific, identifiable reasons. We researched what actually causes it, cited the evidence, and built a checker that reads your file before you waste an hour on an upload that was never going to work.
Your file is read in your browser and never uploaded. No account, no server, no copy of your family's data.
What we measured against
- Maximum file size FamilySearch accepts
- Confirmed limit
- 100 MB
- Individuals per upload FamilySearch recommends
- Official guidance
- 100
- Where silent data loss starts being reported
- Community-observed
- 1,000+
Only the file-size cap is a published limit. See the evidence for each number.
Diagnosis and fix, in the same visit.
Most tools tell you a file is broken and stop there. This one tells you what will fail, why, and then hands you straight into the repair.
Step one
Upload Readiness Checker
Reads your file in the browser and checks size, individual count, encoding, and structural integrity against every documented limit and evidenced failure pattern we could find — then says, in plain language, what will go wrong.
Check a fileStep two
Tree Splitter
If the file is too large, extract a smaller valid one — direct ancestors, a single branch, or everyone born after a given year — carrying the file straight over from the diagnosis without re-exporting from your genealogy software.
Split a tree
GEDCOM Upload Problems & Fixes
Why GEDCOM uploads to FamilySearch and other platforms fail, stall, or silently drop data — the real limits, the exact error text, and what to do about each.
All 18 guides- "Some Records Were Not Uploaded Correctly" — What This Actually MeansFamilySearch's vague "some records were not uploaded correctly" message explained: what's likely missing, why it happens, and how to check what you lost.
- Ancestry: How to Export and Troubleshoot Your GEDCOMAncestry caps GEDCOM uploads at 75 MB, restricts downloads to tree owners, and sometimes hands you a .txt file by mistake. Here's how it actually works.
- Common GEDCOM Upload Error Messages, ExplainedFrom outright rejection to indefinite processing to silent data loss, here's what each FamilySearch GEDCOM upload failure actually means and what to do.
- Exporting Just Your Direct Ancestors: A Step-by-Step GuideA step-by-step walkthrough for extracting only your direct ancestral line from a large GEDCOM file — parents, grandparents, and back — in your browser.
- Family Tree Maker: GEDCOM Export GuideFamily Tree Maker's GEDCOM export never includes publications or tasks, and media links break if the Media folder moves. Here's the full export walkthrough.
Format Reference
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.
- 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.
Data Quality
GEDCOM Data Quality & Cleanup
Finding and fixing broken links, impossible dates, and duplicate individuals hiding in a GEDCOM file — before you import it anywhere or share it with family.
- Cleaning Up a GEDCOM Inherited From a RelativeInherited a GEDCOM file from a relative's old software? Here's a step-by-step workflow for checking, cleaning, and trusting it before you build on it.
- Duplicate Individuals: How They Happen and How to Find ThemDuplicate people are the hardest GEDCOM problem to catch automatically, because the file gives no way to prove it. Here is a workflow that finds them anyway.
- Finding and Fixing Impossible Dates in Your Family TreeDeath before birth, 200-year lifespans, a parent younger than their child — how impossible dates get into a GEDCOM file, and how to track them all down.
- How to Fix Broken Family Links in a GEDCOM FileA broken family link means a GEDCOM pointer only goes one way. Here's how that happens, how to spot it, and how to fix it in your file without losing data.
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