Memdex

About Memdex

Memdex is a Chrome extension that converts your AI conversations into reusable, local memory. It auto-captures chats across ChatGPT, Claude, Gemini and other web-based assistants, stores them encrypted on your laptop (IndexedDB), and offers one-click injection of relevant context into new prompts.

Review

Memdex targets a common friction point: every new chat often requires re-explaining projects, constraints, or preferences. By keeping an encrypted, local copy of past conversations and surfacing relevant snippets inline (similar to how a writing assistant underlines typos), it aims to speed up follow-up work across multiple models without requiring a central account or external vector database.

Key Features

• Auto-captures conversations from multiple web-based AI tools (ChatGPT, Claude, Gemini, Perplexity, Grok) and saves them locally.
• Encrypted on-device storage using IndexedDB so data is not sent to the product's servers, per the product description.
• Inline relevance detection that underlines context in your prompt composer, with a single-click to inject selected memory into the current chat.
• Project-oriented indexing and episodic summaries to surface the most relevant sections rather than entire conversations.
• Free tier keeps the 10 most recent chats; Pro unlocks unlimited saving and access.

Pricing and Value

Memdex offers a free tier that auto-saves your 10 most recent chats and a Pro tier for unlimited storage (specific pricing is available on the product site). The value proposition is straightforward: reduce repetitive context-setting, keep a cross-model history of project details, and maintain that history locally rather than in a third-party cloud. This can save time for people who regularly move between different web LLMs and want consistent context available without manual copy-paste.

Pros

• Local, encrypted storage claimed to keep conversation data on-device rather than uploaded to a central server.
• Works across multiple LLM web apps, so one memory source can serve ChatGPT, Claude, Gemini, etc.
• Inline underlines and one-click injection make applying past context quick and low-friction.
• Clear free tier that lets you try the core workflow before committing to Pro.
• Project indexing and episodic summaries help reduce prompt bloat by selecting relevant snippets.

Cons

• Even though storage is local, injected content is sent to the third-party model when used, which may be a concern for highly sensitive material without fine-grained injection controls.
• Browser-extension integrations can be fragile as web app frontends change, which may require frequent maintenance to keep capture working reliably.
• Desktop-only (Chrome extension) means mobile chats are not captured in real time; syncing mobile-originated conversations may require manual steps.

Memdex is best suited for users who interact with multiple web-based LLMs and want to avoid repeating setup and project context across new chats. It's a practical option for product teams, writers, and knowledge workers who prefer local storage of conversational history and a lightweight way to reuse context; those handling highly sensitive data or relying primarily on mobile workflows should weigh the injection behavior and platform limits before adopting it.