01 — CAPTURE
Inbox for everything
Quick-capture from any app. Web clips, voice memos, PDFs, and fleeting thoughts land in one place and get filed automatically.
Second-brain note taking
Think in pages, not in tabs.
Cortex captures every note, idea, and half-formed thought — then quietly connects them, so the right thing surfaces exactly when you need it.
No credit card · End-to-end encrypted · Mac, Windows, iOS, web
The case for a second brain
Everything you know, in one place
Four capabilities that turn a pile of notes into a mind you can consult.
02 — CONNECT
Links, not folders
Bi-directional backlinks weave each note into the rest of your thinking. Related ideas appear beside you as you write.
03 — RECALL
Semantic search
Ask in plain language. Cortex searches meaning, not keywords — "that pricing insight from the March call," found instantly.
04 — TRUST
Your data, yours
Local-first storage, end-to-end sync, plain-text export whenever you want. No lock-in, ever.
05 — REVIEW
Spaced echoes
Cortex resurfaces old notes at the right interval, so ideas compound instead of rotting in an archive.
06 — SHARE
Publish a thought
Turn any note into a private page or a public essay with one keystroke. Your second brain, on your terms.
It's the first tool that makes me feel like my notes are working back.Maya O. — product researcher
From scattered to systematic in three steps
No methodology degree required.
Dump
Write freely. Cortex handles formatting, tagging, and dates behind the scenes.
Link
Accept a suggested connection and watch two old ideas become one new one.
Ask
Query your own mind. Get sourced answers drawn from years of thinking.
Your best ideas deserve a home.
Join 240,000 thinkers building their second brain with Cortex.
Download Cortex — Free