A private history of every AI you use

Your ChatGPT, Claude, Gemini, Perplexity, and Grok conversations — saved only to your browser, encrypted end-to-end, never uploaded. The local-first alternative to trusting six different retention policies.

In 30 seconds

Most AI tools retain your conversations on their servers, subject to their privacy policies, legal holds, and training-data opt-outs. Memdex is a Chrome extension that keeps its own encrypted local copy of every conversation you have — on ChatGPT, Claude, Gemini, Perplexity, and Grok — so you own a searchable history that never leaves your browser, regardless of what the vendor does with theirs.

  • 100% local storage. Your conversations live in your browser's IndexedDB, encrypted with a key only you hold.
  • Nothing is uploaded to Memdex — ever. No analytics on content, no model training, no cloud sync.
  • Works across five AI tools, so quitting one vendor doesn't erase your accumulated history.
  • Open-source client code; the encryption is inspectable and cannot be silently changed.

What actually happens to your AI chats on ChatGPT, Claude, and the rest

You can already tell ChatGPT not to train on your chats, delete your account, or switch to a private LLM. What none of those options give you is your own copy of everything you already said. That's the gap Memdex fills — a local archive that outlives any single vendor relationship.

RETENTION

You don't control how long your conversations are kept

OpenAI, Anthropic, Google, Perplexity, and xAI each publish different retention windows — and they change. Legal holds, like the 2025 NYT v. OpenAI preservation order, can also override the 30-day deletion default. The only retention policy you fully control is the one on your own disk.

OPT-OUTS ARE MANUAL

Training opt-outs are per-product and easy to forget

ChatGPT has one toggle, Claude has another, Gemini a third. Switching devices or accidentally signing in on a fresh browser can reset them. One missed click and the next conversation is training data.

PRIVATE LLMs ≠ PRIVATE HISTORY

A private AI doesn't help with the conversations you've already had

Maple, Lumo, and Okara give you a private model — but they start from zero. Years of ChatGPT threads that you want to keep are still sitting on someone else's server.

LOCAL-ONLY

Your copy should be yours alone

Memdex takes the opposite approach: don't move you off the tools you use, just make sure you own a faithful, encrypted record of everything you say in them. No account required, no cloud tier.

How Memdex keeps your AI history private

The design principle: nothing we build should ever need your conversations to leave your browser.

01LOCAL CAPTURE

Conversations stay on your device

Memdex observes the pages you already have open — ChatGPT, Claude, Gemini — and copies each message into your browser's IndexedDB. There's no Memdex server that sees your conversations, because there's no path for them to leave.

02ENCRYPTED AT REST

Encrypted with a key only you hold

Every saved message is encrypted with AES-GCM using a key derived from a secret on your device. Even a machine attacker would need that local secret to read anything — we cannot read it, because we never see it.

03NO ACCOUNT

No sign-up, no cloud sync, no telemetry on content

You can use Memdex without creating an account. The extension ships without any analytics on your conversations; the only metrics we see are install counts and error traces — never the content of a chat.

How Memdex compares on privacy

Different tools sit at different places on the privacy ladder. Memdex stays on the rung where your conversations don't leave your machine.

CapabilityMemdexChatGPT (temporary chat)MemoryVaultMaple AI
Keeps your ChatGPT, Claude, and Gemini conversations
Storage never leaves your device
Works with the AIs you already pay for
No account required
Encrypted at rest with a user-held key
Can inject past context into new chats

ChatGPT temporary chats are not shown in history and are not used for training, but still transit OpenAI servers during the session and may be retained up to 30 days under legal hold. Maple AI offers private LLM chat but not a private history of other tools.

Frequently asked

Every saved conversation lives in your browser's IndexedDB on the machine you installed the extension on. It is encrypted at rest with a key derived from a local secret, never synced to a Memdex server, never shared with a third party, and never used for training. If you uninstall the extension, the data goes with it.

Keep your AI history. Without trusting anyone.

Private AI conversation history, stored 100% locally | Memdex