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Arcanum

Arcanum

Share secrets securely

End-to-end encrypted. No storage. No accounts. Auditable code.

Try it now

No signup required

Relay: ?

Your secret is encrypted in the browser before sending. The relay only passes through the encrypted data.

Why trust this?

The code is tiny. Read it yourself.

~60
lines in server
~55
lines of crypto
1
dependency
0
data stored

No frameworks. No build step. You can audit the entire thing in 10 minutes.
View source on GitHub

How it works

RSA-OAEP 2048-bit encryption, all in your browser

1
Receiver clicks "Receive"

Browser generates RSA keypair. Private key stays in memory.

2
Share the public key

Copy the arc1pk_... key and send via Slack, email, etc.

3
Sender encrypts & sends

Secret encrypted in browser, sent through relay as encrypted blob.

4
Receiver decrypts

Browser decrypts with private key. Keys destroyed after use.

The server is a dumb pipe. It forwards encrypted data without being able to read it.
View app.js

Why not just use...

DM Logged forever
Email Stored on servers, often unencrypted in transit
Signal Both parties need accounts and the app
PGP Let's be honest, nobody has it set up
Password Manager Paid subscription, both need accounts
Arcanum Open browser. Share key. Done.