Talk in private.
End-to-end encrypted messages with post-quantum key exchange — and no phone number. Reach anyone on the Logos iOS app from right here in your browser.
Create your identity
Already have an account on the iOS app? Cross-device restore is coming next — for now, create a fresh web identity.
Find someone
Look up anyone registered on Logos (including iOS users) and check their safety number.
Private messaging, built to outlast the quantum era
Logos is an end-to-end encrypted messenger with no phone number. Every conversation is sealed on your device — the relay only ever forwards unreadable envelopes, on the web and on iOS.
Post-quantum key exchange
Sessions begin with PQXDH — a hybrid of classical X25519 and ML-KEM-1024. An attacker would have to break both, so messages captured today stay private against tomorrow's quantum computers.
End-to-end encrypted
A Double Ratchet rekeys every message with forward secrecy and post-compromise security, sealing it with ChaCha20-Poly1305. Only you and the person you're talking to can read it.
Sealed sender
The relay is minimal-trust: it stores public keys and sealed blobs, never plaintext, and sealed-sender certificates keep it from learning who is messaging whom.
No phone number
Pick a username. No phone number, no email, no contact upload — your identity isn't tied to a SIM card.
Keys never leave your device
Identity and message keys are generated locally in your browser and stored only there. The server never sees a private key.
Verify with safety numbers
Compare a safety number with anyone — including people on the iOS app — to confirm there's no machine in the middle of your conversation.
How it works
- 1Create an identity. Pick a username — your keys are generated right here in your browser.
- 2Save your recovery secret. It's the only way to restore your identity if you lose this browser; we can't recover it for you.
- 3Find someone and chat. Look up a username, check the safety number, and start an end-to-end encrypted conversation — on web or iOS.
Frequently asked questions
Is Logos really end-to-end encrypted?
Yes. All encryption happens on your device, and the relay only ever holds sealed, unreadable envelopes — it never sees message plaintext. Logos is still experimental and unaudited, so don't rely on it for high-stakes secrets yet.
Do I need a phone number?
No. You pick a username — there's no phone number, no email, and no contact upload.
What is post-quantum key exchange?
Logos starts every session with PQXDH, a hybrid handshake combining classical X25519 with ML-KEM-1024. Breaking it requires breaking both, so messages captured today stay private even against a future quantum computer — defeating "harvest now, decrypt later."
Can I message people on the Logos iOS app?
Yes. The web client and the iOS app share the same network — look up any Logos username, verify the safety number, and start chatting.
What if I lose my recovery secret?
Your identity can't be recovered. Keys live only on your device, so no one — including us — can reset your account. Keep your recovery secret somewhere safe.