ChatStash

ChatStash is a free browser extension for Chrome and Firefox that backs up AI conversation history from ChatGPT, Claude, and Gemini. It is built for people who want those chats preserved locally on their own device instead of only on a service’s server.

The extension runs in the background and automatically saves every standard chat conversation from those platforms. It keeps code blocks, markdown formatting, generated images, and the surrounding conversation context, and it stores everything in the browser’s IndexedDB. ChatStash also supports searching saved conversations by keyword, date, or platform, including searches within code and formatted text. Users can filter by platform or date range, sort by creation or update time, view full message history in the sidebar, export a single conversation or the entire archive to JSON, delete individual conversations, and clear all data with confirmation steps. It also offers settings to enable or disable backups for specific platforms, control save notifications, set auto-delete rules for old conversations, and view storage statistics.

ChatStash is described for developers who want to save code solutions, debugging sessions, algorithm explanations, and API examples; researchers and students who want to archive literature summaries, concept explanations, methodology discussions, and study materials; writers who want to keep brainstorming sessions, draft iterations, editing suggestions, and creative explorations; and anyone who regularly returns to past AI chats. It works with ChatGPT, including GPT-4 and deep research, Claude, including Opus, Sonnet, and Haiku, and Google Gemini, and it is available from the Chrome Web Store and Firefox Add-ons. The extension is free, uses no cloud sync, makes no API calls, and does not send data to external servers.