Chats with these models are work product now, and all four platforms can take them away: account bans, accidental deletion, or history that quietly stops being served. I went through the native export path on every platform. All four exist, none is complete, and two have traps. Written up so you can set a schedule and forget it.
ChatGPT
Settings, then Data controls, then Export data. A zip arrives by email: conversations.json with everything, and chat.html, the whole history as one page. Link expires in 24 hours. Gaps: one blob, no per-conversation files, and the wait ranges from minutes to days on big accounts.
Claude
Settings, then Privacy, then Export Data. A zip of JSON arrives by email, usually within minutes, covering conversations and projects. Same 24 hour link expiry. Gaps: memory entries are not included, and again one blob of JSON rather than per-chat files.
Gemini
takeout.google.com, and here is the trap: the product listed as Gemini exports your Gems configuration, not your chats. Deselect all, pick My Activity only, narrow it to Gemini Apps, and switch the format from the default HTML to JSON. You get MyActivity.json, an activity log with one record per prompt and response. Gaps: it is a log, not conversations, there is no per-chat structure at all, and history that Gemini's backend no longer serves is not in it.
Grok
The only one with no export in the product. What exists is the xAI account data download at accounts.x.ai/data, sign in with the account you use for Grok and request the archive, which is reported to include grok.com conversations as JSON. For Grok used inside X, coverage through the X data archive is inconsistent in my testing, so if someone here has a definitive recent result, that is a genuinely useful comment.
The pattern across all four: the native exports are account-level compliance features, not archival tools. They give you everything as one undifferentiated blob, on a link that dies in a day, in formats built for lawyers rather than for reading. None gives you a single conversation as a file, and none does Markdown or PDF. For per-chat files I use a browser extension I work on (AI Toolbox), which exports individual or bulk conversations as TXT, Markdown, JSON or PDF on all four platforms, and I will leave it at that since this post is about the native paths.
My schedule, for what it is worth: native export from each platform on the first of the month into a dated folder, checked once that the zip opens, never read again. The blob is the insurance, the per-chat files are the working copies.
What are people's retention setups for AI chats? I have not seen a good answer for diffing two monthly ChatGPT blobs to find what changed, and I suspect someone here has already scripted it.