# GEDCOM Tools

> Browser tools for inspecting and repairing GEDCOM 5.5, 5.5.1 and 7.0 files, plus optional
> private hosted storage, deterministic checks and HTML reports. Browser parsing stays on your
> device. Hosted uploads require consent and remain private until deletion. Optional browser
> model actions send disclosed extracts through OpenRouter after approval. Keep the original.

## What makes this different from other GEDCOM tools

- Reading a file and writing it straight back returns the same bytes, including byte-order marks,
  mixed line endings, over-length lines split across CONC and CONT, and tags no standard defines.
- Review changes before exporting a separate file. Merge reversal requires compatible retained
  history; keep the original rather than relying on another program to preserve that history.
- Supported determinations travel in the GEDCOM. Other programs may remove their carriers;
  check an exported and re-imported copy before relying on them.
- Read the signals, confidence and limitations a tool supplies. Scores do not establish identity.

## Free tools

- [Corrupted File Recovery](https://gedcom.tools/gedcom-file-recovery): Rebuilds a file that other programs refuse to open, and lists every dropped byte with its offset, its hex and the reason.
- [Dialect Report](https://gedcom.tools/gedcom-dialect-report): Names the program that wrote the file, and warns which custom tags each of six destinations will drop.
- [Duplicate Individual Finder](https://gedcom.tools/duplicate-finder): Finds people entered twice by name, date, place and family, and tells a duplicate from a child named after a dead sibling.
- [Encoding Repair](https://gedcom.tools/gedcom-encoding-repair): Finds the character set the file was really written in, and rewrites mangled text such as "Müller" as clean UTF-8.
- [File Inspector](https://gedcom.tools/inspect): Shows the GEDCOM version, the producing program, the encoding and the record counts, with every problem the parser noticed.
- [Format Converter](https://gedcom.tools/gedcom-converter): Converts a file between GEDCOM 5.5.1 and 7.0, and lists every construct the target version cannot hold.
- [GEDCOM Preflight Report](https://gedcom.tools/gedcom-preflight-report): Runs seven import checks and downloads a self-contained HTML report of blockers, warnings and repairs without uploading the GEDCOM.
- [GEDCOM Validator](https://gedcom.tools/gedcom-validator): Checks a file for structural, referential and logical errors, and names the record, the line and the tool that fixes each one.
- [GEDCOM Viewer](https://gedcom.tools/gedcom-viewer): Opens the file as people, families, pedigrees and timelines, with every name and tag as the source wrote it.
- [Impossible Fact Fixer](https://gedcom.tools/impossible-fact-fixer): Separates dates that cannot be true from dates that are merely unusual, and proposes a reversible fix with the arithmetic.
- [Link Reciprocity Checker](https://gedcom.tools/link-reciprocity-checker): Finds family pointers the other record never answers, and sorts each into probable duplicate, orphan or incomplete entry.
- [Relationship Calculator](https://gedcom.tools/relationship-calculator): Names the kinship between two people in both directions, and shows the parent and child steps behind the answer.
- [Subtree Extractor](https://gedcom.tools/subtree-extractor): Extracts a standalone file around one person, ancestors or descendants to the depth you choose.
- [Tree Health Score](https://gedcom.tools/tree-health-score): Scores a tree 0 to 100 on completeness, sourcing and consistency, and lists the records that cost it points.

## Pro tools

- [Broken Link Repair](https://gedcom.tools/broken-link-repair): Finds pointers to records that do not exist, and proposes a delete, a repoint or a placeholder for each one.
- [Citation Parser](https://gedcom.tools/citation-parser): Reads archive identifiers out of free-text citations, and proposes a structured source record for each one.
- [Date Normaliser](https://gedcom.tools/date-normaliser): Rewrites dates into the standard form across five calendars, and flags every reading the digits do not settle.
- [Determination Ledger](https://gedcom.tools/determination-ledger): Lists every merge, verdict and negative finding written into the file, and reverts any of them.
- [Living Person Privatiser](https://gedcom.tools/living-person-privatiser): Decides who is still living and redacts them, then checks the output for addresses, phone numbers and leaked names.
- [Media Portability Workbench](https://gedcom.tools/media-portability-workbench): Finds missing media files and previews path repairs.
- [Merge Conflict Arbitration](https://gedcom.tools/merge-arbitration): Argues both sides of one duplicate pair with a language model, which answers merge, do not merge, or not enough evidence.
- [Merge Workbench](https://gedcom.tools/merge-workbench): Compares two people field by field, and merges them into one record as a single patch you can undo.

## Studio tools

- [Note Structurer](https://gedcom.tools/note-structurer): Reads the prose notes in a file, and turns the hypotheses and corrections they carry into determinations you accept one by one.
- [Research Gap Planner](https://gedcom.tools/research-gap-planner): Finds records the tree implies but never cites, and names the archive, the parish and the year range to search.

## How-to guides

Each one answers at the same address with `.md` appended, which returns the article's own markdown.

- [What is a GEDCOM file](https://gedcom.tools/how-to/what-is-a-gedcom-file): A plain text format for exchanging family trees. Learn how its records and pointers work, and what to check before another program imports it. beginner, 10 minutes.
- [Read a GEDCOM without installing anything](https://gedcom.tools/how-to/read-a-gedcom-without-installing-anything): Someone emailed you a .ged file. Open it as people, families and a pedigree in a browser tab, with nothing uploaded and nothing installed. beginner, 10 minutes.
- [How to check a GEDCOM before you import it anywhere](https://gedcom.tools/how-to/check-a-gedcom-before-you-import-it-anywhere): Start with a local preflight report, review structure, links, media and privacy, then check the exact file you plan to import. beginner, 30 minutes.
- [How to work out what a GEDCOM file actually contains](https://gedcom.tools/how-to/work-out-what-a-gedcom-file-actually-contains): Someone sent you a .ged and you have no program to open it. Read the version, the producer, the charset, the counts, the custom tags and the people, in order. beginner, 20 minutes.
- [How to fix a GEDCOM file that will not open](https://gedcom.tools/how-to/fix-a-gedcom-file-that-will-not-open): Inspect an import failure, review structural recovery and its loss report, then validate the output before a test import. Keep the original export. beginner, 15 minutes.
- [How to fix garbled characters and accents in a GEDCOM](https://gedcom.tools/how-to/fix-garbled-characters-and-accents-in-a-gedcom): Müller reads as Müller, or as M?ller. Compare charset detection and proposed corrections, preserve the original, and check the UTF-8 output. beginner, 15 minutes.
- [GEDCOM error messages, decoded](https://gedcom.tools/how-to/decode-gedcom-error-messages): Use an import error as a starting point. Check the file's structure, encoding and pointers before choosing a repair, and review what recovery changes. beginner, 15 minutes.
- [What is ANSEL, and why your names look wrong](https://gedcom.tools/how-to/what-is-ansel-and-why-your-names-look-wrong): Your file says 1 CHAR ANSEL and the accents came out as separate marks. ANSEL puts the accent before the letter, and Unicode puts it after. intermediate, 15 minutes.
- [How to remove living people before sharing your family tree](https://gedcom.tools/how-to/remove-living-people-before-sharing-your-family-tree): Decide who is living, redact them, and check the exported file for the addresses, phone numbers and names that hide in free text. Every verdict comes with its rule. intermediate, 20 minutes.
- [How to split one branch out of a large family tree](https://gedcom.tools/how-to/split-one-branch-out-of-a-large-family-tree): Pick a root and generation limits, review the people and references included, then validate and privatise the extracted GEDCOM before sharing. beginner, 15 minutes.
- [How to prepare a GEDCOM for Ancestry, MyHeritage, FamilySearch or GEDmatch](https://gedcom.tools/how-to/prepare-a-gedcom-for-ancestry-myheritage-familysearch-gedmatch): Review dated compatibility warnings, protect living people's details, choose a supported GEDCOM version, and test an import before moving your tree. intermediate, 30 minutes.
- [How to prepare a GEDCOM for GEDmatch](https://gedcom.tools/how-to/prepare-a-gedcom-for-gedmatch): Prepare the branch you intend to share, redact living people's details, review privacy limits, and validate the file before a GEDmatch upload. intermediate, 25 minutes.
- [Which custom tags your destination may lose](https://gedcom.tools/how-to/what-each-site-deletes-from-your-gedcom): Compare dated compatibility warnings for six destinations. Count the custom tags at risk, check the evidence, and test what your import route preserves. intermediate, 20 minutes.
- [How to find and fix missing media links in a GEDCOM](https://gedcom.tools/how-to/find-and-fix-missing-media-links-in-a-gedcom): Compare GEDCOM media paths with a folder on your device, review ambiguous matches, and download a corrected file without uploading photos. beginner, 15 minutes.
- [How to find and merge duplicate people in a GEDCOM](https://gedcom.tools/how-to/find-and-merge-duplicate-people-in-a-gedcom): Review duplicate candidates and their evidence, merge confirmed pairs, and export the decisions and undo data. Keep a pre-merge backup. intermediate, 30 minutes.
- [How to tell a duplicate from a child named after a dead sibling](https://gedcom.tools/how-to/tell-a-duplicate-from-a-child-named-after-a-dead-sibling): Review same-named siblings without merging them on shared parents alone. Check the dates, sources and limits of the necronym heuristic. advanced, 25 minutes.
- [How to undo a merge you should not have made](https://gedcom.tools/how-to/undo-a-merge-you-should-not-have-made): Restore a merge from its exported inverse when the data survives and still matches. Check recovery limits, preserve backups, and validate the restored records. intermediate, 15 minutes.
- [How to find every broken pointer in a GEDCOM](https://gedcom.tools/how-to/find-every-broken-pointer-in-a-gedcom): Find missing and wrong-type pointer targets, review delete, repoint and placeholder options, then check reciprocal family links in the repaired output. intermediate, 20 minutes.
- [Why your dates changed when you uploaded](https://gedcom.tools/how-to/why-your-dates-changed-when-you-uploaded): Check numeric date order, calendar conversion and chronology findings. Review ambiguous readings against records before changing dates in your export. intermediate, 20 minutes.
- [How to turn free-text source notes into real citations](https://gedcom.tools/how-to/turn-free-text-source-notes-into-real-citations): Recognize supported archive identifiers, review source-record proposals, and preserve the original citation wording without treating a parsed reference as proof. advanced, 30 minutes.
- [How to plan your next genealogy research steps](https://gedcom.tools/how-to/plan-your-next-genealogy-research-steps): Find gaps in your GEDCOM, review archive suggestions, and save a research plan. Use optional AI ordering without treating suggestions as evidence. intermediate, 20 minutes.
- [How to convert GEDCOM 5.5.1 to 7.0, and what does not survive](https://gedcom.tools/how-to/convert-gedcom-5-5-1-to-7-0-and-what-does-not-survive): Compare version mappings and unrepresentable structures before converting. Review extension or drop choices, validate the output and keep the original. intermediate, 20 minutes.

## For agents

- [API reference](https://gedcom.tools/api): public discovery and seven authenticated hosted operations with REST parity, scopes and limits. Hosted operations make no paid AI calls.
- [Remote MCP](https://gedcom.tools/mcp): Streamable HTTP for unauthenticated public discovery and scoped private uploads, analysis, reports and deletion.
- [Hosted access](https://gedcom.tools/hosted-access): complete onboarding before creating a private vault.
- [Vault and scoped keys](https://gedcom.tools/vault): save your owner key, issue read/write/delete agent keys and delete retained files. Use Authorization: Bearer <AGENT_TOKEN>; keep the owner key out of agent configuration. See the MCP guide for consent and cleanup limits.
- [Tool manifest](https://gedcom.tools/tools.json): every tool as JSON, with what it needs, whether it changes your file, whether it sends anything to a model, what has to run before it, and the words people use when they want it.
- [Use with AI](https://gedcom.tools/for-agents): copy the whole guide or one tool prompt; check privacy, evidence and approval boundaries.
- [Genealogy Research skill](https://www.skills.sh/sliday/genealogy-research): the canonical research workflow for your own agent.
- [Genealogy Research source](https://github.com/sliday/genealogy-research): installation instructions and skill source.
- [Use GEDCOM Tools with your AI agent](https://gedcom.tools/for-agents/overview): Ask your agent to choose a browser tool, interpret a report or plan source-backed research.
- [Discovery files for AI agents](https://gedcom.tools/for-agents/llms): Use these public files to find the right GEDCOM Tools page without loading a private tree:
- [Hosted MCP and REST access](https://gedcom.tools/for-agents/mcp): Use remote MCP for public discovery and authenticated checks on a GEDCOM retained in your private vault.
- [One prompt per tool](https://gedcom.tools/for-agents/prompts): Choose one of the 24 prompts and paste it into your browser-capable agent.
- [Genealogy research skill](https://gedcom.tools/for-agents/skill): Use Sliday's canonical genealogy-research skill with your own agent.
- [Report a bug or ask for a tool](https://gedcom.tools/feedback): challenge-protected feedback form. Avoid private GEDCOM content.

## Optional

- [What these tools promise](https://gedcom.tools/about): the seven rules every tool is built and tested against.