Real-time related notes
As you write, ZettelNote quietly surfaces past notes that are actually related — often before you even remember writing them.
Features
Semantic search
Find related notes even when the wording doesn't match, thanks to embedding-based semantic search. Pick a lightweight model or a more accurate multilingual one, whichever fits how you write.
Zero-knowledge encryption
Your notes are encrypted on your device with AES-256-GCM before they ever reach our servers. Not even we can read them.
Desktop + web
Native desktop apps for Windows, Mac, and Linux, plus an installable web app (PWA) that works offline.
Multi-device sync
Start on your laptop, keep going on your phone. Changes sync automatically and show up in real time on every device.
Tags & keyword search
Plain #hashtags and simple keyword search are still there for when you just want to find something fast.
How it works
What's a Zettelkasten?
Zettelkasten ("slip box" in German) is the note-taking method behind sociologist Niklas Luhmann's remarkably prolific output, and the inspiration for the modern second brain and PKM (personal knowledge management) movement. Instead of sorting notes top-down into folders, you build a web of connections bottom-up, note by note — insight tends to show up later, when you rediscover links you didn't consciously make. ZettelNote automates that connecting part, so you don't have to link every note by hand.
How the encryption works
Everything you write is encrypted on your device — in your browser or the desktop app — with AES-256-GCM before it's ever sent anywhere. Your encryption key is derived from your own passphrase, locally, and never leaves your device. We only ever store encrypted data, so even if our database were compromised, your notes stay unreadable without your passphrase.
Semantic search models
Related notes are found two ways: a fast bigram search that catches notes with similar wording, and a multilingual embedding model that finds notes with similar meaning even when the words are completely different. The lightweight option runs at essentially no cost; the accurate one is a good fit if you write across multiple languages or paraphrase a lot.
Start connecting your notes.
Sign-up is free — or try it instantly with no account at all.
Open ZettelNote