caırn Open Cairn
Free No account. No limits. Yours on disk.

Stack up everything
worth keeping.

Links, notes, photos, PDFs and voice notes in one calm library. Saved in a second, found in two, and still yours the day you leave.

Start your library → Explore the demo

Any browser  ·  Chrome extension  ·  MCP for your AI tools

cairn.uxasim.com/app
One library

Every kind of thing you keep,
in one place.

Stop scattering links across tabs, notes across apps and voice memos across your phone. Cairn turns each one into a card you can see at a glance.

Capture

Save it the moment you find it.

Four ways in, none of them slower than a second. Cairn works out what you saved and files it.

Link detected · nngroup.com

Paste or type

Drop a link, write a line, or press N. The first line becomes the title.

Save to Cairn
Why small software stays small
Save ↵
CtrlShiftS

One click in Chrome

The extension saves the page, a highlighted quote or any image. Get it →

0:07

Say it out loud

Press V and talk. You see your level as you speak, and the note keeps its waveform.

Drop an image

Drop a file

Drag in a photo or paste a screenshot. It lands as a full-size card in your Inbox.

Resurface

Old saves come back to visit.

Every morning Cairn brings back three things you saved more than a month ago. Keep the ones that still matter. Let the rest go without guilt.

Try it: press Keep or Let go.

New · Voice notes

Talk instead of typing.
Listen back anywhere.

Some ideas arrive faster than you can type them. Record them straight into your library and play them back right on the card.

  • Press V anywhere in Cairn to start recording
  • Play on the card, jump around the waveform in the reader
  • Listen at 1×, 1.5× or 2×
  • Whatever you typed becomes the title and notes
  • Kept as a real audio file in your library folder
Record your first note
Kitchen idea — apricot jamVoice note · Kitchen · saved Tuesday
0:00 / 0:14

Note to self for the weekend. Halve the sugar in the apricot jam, add a squeeze of lemon at the very end, and keep two jars back for Nani. Label them with the date this time.

This sample is read aloud by your browser's own voice. Notes you record play back your real audio.
Plain files

A folder you own,
not a server you rent.

Pick a folder and Cairn keeps it in sync. Every save is a small JSON file with a Markdown copy beside it. Photos and voice notes sit next to them as ordinary images and audio.

Back it up, sync it with any drive, search it with any tool. If Cairn vanished tomorrow, your library would still open.

My Library
  • { }cairn.json library settings
  • { }spaces.json
  • ▾items/
    • MDkitchen-idea-apricot-jam.md
    • { }kitchen-idea-apricot-jam.json
    • ♪kitchen-idea-apricot-jam.webm
    • ▣karimabad-at-night.webp
    • MDprogressive-disclosure.md
    • + 212 more
  • ▸agents/ who may read, who may write
Built for agents

Hand your library to your AI tools.

Cairn ships a tiny command-line tool that is also an MCP server. Claude, Cursor or any other MCP client can search your saves, read them and, only if you allow it, add new ones.

  • Read-only unless you switch writing on
  • Never deletes for good, never rewrites your text
  • One file, nothing to install beyond Node 18
Connect an agent
Terminal
$ node cairn.mjs find hunza --kind image
● Karimabad at night  Hunza trip · #travel
● Apricots piled high Hunza trip · #food

$ claude mcp add --scope user cairn -- node cairn.mjs mcp serve
# Claude can now search and read your library.
# Add --allow-write if it may save new things too.
Cairn for

One library, shaped by what you keep.

Our promises

No catch. Here's what we mean.

  1. Free for everyone.No plan, no trial, no item cap. Every feature on this page is included.
  2. No account.Open the app and start. There is nothing to sign up for and no password to forget.
  3. Nothing leaves your device.Your library lives in your browser and, if you pick one, a folder on your computer.
  4. Leave whenever you like.Export everything as one file in one click, or simply keep the folder.
  5. No tracking.No analytics scripts, no ads, nothing about you is sold.

Start your cairn.
One stone at a time.

Save the next thing you'd hate to lose. It takes about a second.

Start your library →Explore the demo