Uni3K · Card notes
What you find and what you think, kept as cards.
Uni3K is card notes for Chrome, Edge and the web. Keep a passage from the web with its source, or jot a thought in a few lines. Come back to them later by date or by search, and let your own AI look things up too.
The idea
A clean corner of the web
The web is huge and noisy. Uni3K holds only what you chose to keep and what you wrote yourself.
Glimpses through time
What you saw becomes a clip, what you thought becomes a quick note. Look back over them by day, week or month.
Friendly to AI agents
Your AI can search the cards you allow and keep notes in a space of its own. Locked cards stay closed to it.
Features
Clip in one click
Select text on any page, then tap the + next to it, press Alt+C or right-click and choose Save to Uni3K. The page title and link come with it, and the passage is highlighted when you visit again.
Quick notes
Press Alt+S or click the toolbar button to open the side panel, write a thought and press Ctrl/⌘+Enter. Attach the current page if you like.
Markdown
Headings, lists, checklists, quotes, links and code blocks, in every card.
Look back over time
Browse your cards by day, week or month, or see them all at once in a masonry view.
Find it again
Full-text search over everything you kept, plus folders to sort cards the way you think.
Your AI can search and write
Turn on local MCP and assistants such as Claude, Codex or Cursor can search the cards you allow and save Agent cards in their own space. How it works
Lock private cards
Lock a card with your own password. It is encrypted on your device and never readable by search, sync services or AI. Nobody can recover a forgotten password, including us.
You choose where cards live
Local by default, no account needed. Sign in for cloud cards that follow you to every browser and the web app, or sync through your own WebDAV or Google Drive.
Web app and canvases
At app.uni3k.com you can read and edit your cloud cards anywhere, and lay cards out on a canvas. Free to start.
Backups that are yours
Export everything as a file at any time, restore a local snapshot, or bring an export back in. Deleted cards wait in Trash first.
Quiet by design. No ads, no analytics, no tracking. The extension installs without access to all websites, and asks for more only when you turn a feature on, such as the + button or local MCP.
Where it works
- Chrome 116 or later and Microsoft Edge on Windows, macOS and Linux. Brave and other Chromium browsers usually work too.
- The web app at app.uni3k.com works in any modern browser and shows your cloud cards.
- The interface is in English, 简体中文 and 日本語.
- Browser pages, extension stores and some protected pages cannot be clipped. This is a browser rule.