Build your family tree with ChatGPT (free, starting tonight)

The 4-step build 🌳

1. 🗂️ Map what you already know. Open ChatGPT and let it interview you, then draft a clean starter tree from your side of the family. Feeding it real facts you know beats asking it to guess. This is your foundation before any searching happens.
2. 📜 Point you to the records. Have it read your surname and family origins and tell you which record sets are worth chasing (census, parish, immigration, military) and where they live, with what is a documented lead versus an educated guess. ChatGPT is great at telling you where to look, not at naming a specific ancestor.
3. 🔎 Let it dig the open web. Turn on ChatGPT Work so it opens its own browser and pulls obituary and public-record leads, each one with a source link you can click. On the free plan, run the same searches in a normal chat and open each link yourself.
4. 🌳 Get a clean chart, then verify. Ask it for your tree as Mermaid code and render it free (below), then confirm every new name on FamilySearch before you treat it as real.

The 4 prompts 📋

Run them in order in the same chat, so ChatGPT keeps the context of your tree as it grows.

I'm building my full family tree, and I want you to interview me first.

Ask me everything you need, one batch at a time: my full name, where my family is from (country, region, town), and every relative I can remember on both sides, with names, rough birth and death years, and how each one is related.

Then organise everything I tell you into one clean starter tree, grouped by generation, and flag the gaps where I clearly don't have a name or a date yet.

Based on my surname and my family's origins, tell me where to research my family line, as far back as the records reasonably allow.

Explain what the surname's history and migration patterns suggest, which record sets would cover my regions and time periods (census, parish, immigration, military), where those records actually live, and the specific leads worth chasing next. Be clear about what is a documented lead versus an educated guess. Do not invent specific ancestors or records.

Search free public records and obituaries for relatives I don't have yet, and link each source.

Stick to the free open web: obituary archives, cemetery and memorial sites like Find a Grave and BillionGraves, free public-record indexes, Chronicling America and other free newspaper archives, and the free FamilySearch tree. For every person you find, give me the name, the dates, how they connect to my tree, and the exact source link. Do not present anything as confirmed, treat each one as a lead for me to verify, and if you are not sure, say so instead of guessing.

Now turn my family tree into a clean visual. Output it as Mermaid diagram code (a graph TD block), top-down and grouped by generation, with each person's name and their birth and death years.

Mark confirmed people and unverified leads differently (for example, add a question mark to the unverified ones). Give me only the Mermaid code inside a code block, so I can paste it straight into a renderer.

3 things that make it a real family tree 🌱

1. 🎙️ Capture the oral history first, before it's gone. This is the one input you can never get back. Record a 20-minute chat with your oldest relatives on your phone's voice memo app (free), then transcribe it free with Otter.ai (300 minutes a month free), or just talk it through with ChatGPT's voice mode. Then paste the transcript in: "Pull out every name, date, place and relationship into a clean list, and flag what I should ask them to clarify next time." Maiden names and village names live in people's memories, not in records.
2. 🖼️ Bring the old photos back to life. Restore, sharpen and colourise faded family photos. Honest heads-up so you don't get pushed to pay: MyHeritage In Color and its Photo Enhancer are built for exactly this but watermark the free previews and cap the free count, and Palette.fm gives one free high-res colourised download. For viewing and sharing on your phone the free previews are plenty, only pay if you want a print-quality copy of a hero photo.
3. 🧱 Break through a brick wall. When a name just stops, no tool needed. Ask ChatGPT for "10 likely spelling and transcription variants of this surname for old records" (names got misheard constantly). Search sideways, not just up: a missing ancestor often shows up in a sibling's or in-law's record. Chase records that name a birthplace (immigration, naturalisation, military). And use Find a Grave to spot family buried together, headstones often reveal maiden names and relationships.

Save your tree so it isn't trapped in a chat 💾

A tree living inside a ChatGPT conversation vanishes when the chat does. Build the permanent version free on FamilySearch, it hosts your tree online forever and auto-connects it to records. Keep a plain backup too: ask ChatGPT to output your tree as a simple table you paste into a Google Doc. If you ever move between apps, the universal family-tree file format is called GEDCOM, that's the word to search.

Verify every name on FamilySearch (free) 🆓

This is where a fun rabbit hole becomes a real tree. ChatGPT finds the leads, but you confirm them against actual records, and it does hallucinate, even with browsing on, so every name is a hypothesis until you see it on a real record. Your free home base is FamilySearch, and here is the free-versus-paid map so you never get pushed toward a subscription you don't need.