Military-Grade EncryptionFor Every Single Message.
Zitto is built on Signal Protocol — the gold standard in private messaging cryptography. Every conversation uses X3DH key exchange and Double Ratchet encryption, ensuring only you and your recipient can ever read your messages.
How Zitto's Encryption Works
When you send a message in Zitto, it is encrypted on your device before it leaves. The encryption key is derived using X3DH (Extended Triple Diffie-Hellman) — a protocol that securely establishes a shared secret between two parties without ever transmitting the secret itself over the network.
Once a session is established, the Double Ratchet Algorithm takes over. It continuously generates new encryption keys for each message — a process called forward secrecy. This means that even if an attacker somehow obtained the key for one message, they could not use it to decrypt any other message, past or future.
Zitto's servers act as a relay for encrypted blobs only. We receive ciphertext, forward it to the recipient, and that's it. We cannot decrypt, search, or analyze your messages — the keys never leave your device. Read our complete guide to encrypted messaging for a deeper look at how these protocols protect your privacy end to end.
Cryptographic Pillars of Zitto Security
X3DH Key Exchange
Extended Triple Diffie-Hellman establishes a shared secret between you and your contact — even if one party is offline at the time.
Double Ratchet Algorithm
Every message uses a new encryption key derived from the previous one. Even if one key is compromised, past and future messages stay safe.
Safety Numbers
Verify your contact's cryptographic fingerprint in person or via a secondary channel to ensure no one is intercepting your messages.
Forward Secrecy
Keys are ephemeral. Old keys are discarded continuously, meaning past messages cannot be decrypted even if your device is later compromised.
Zero Server Knowledge
Zitto's servers relay encrypted blobs. We never hold your plaintext messages, encryption keys, or the ability to decrypt your conversations.
Open Protocol
Built on Signal Protocol — the same proven cryptographic standard used by the most trusted private messaging apps in the world.
The Same Encryption Standard Used by the World's Most Trusted Apps
Signal Protocol was developed by Open Whisper Systems and is used by secure messaging applications around the world. Zitto implements the same open, audited, battle-tested cryptographic standard — not a proprietary or unvetted alternative.
Open-source cryptography. No proprietary black boxes. No backdoors.
Frequently Asked Questions
What is end-to-end encryption?
End-to-end encryption (E2EE) means only you and your recipient can read messages. Data is encrypted on your device and can only be decrypted by the intended recipient — no one in between, including Zitto, can read it.
What is Signal Protocol?
Signal Protocol is a set of open-source cryptographic specifications developed by Open Whisper Systems. It combines X3DH key exchange with the Double Ratchet algorithm to provide forward secrecy and break-in recovery.
Does encryption apply to group chats too?
Yes. Each group conversation in Zitto uses per-group encryption keys. Every member's device holds a copy of the group key, and messages are encrypted before leaving your device.
What are Safety Numbers?
Safety Numbers (also called fingerprints) are a unique code generated from your and your contact's public keys. Comparing them out-of-band confirms your conversation has not been intercepted by a man-in-the-middle attack.
Can Zitto read my messages?
No. Zitto servers only see opaque encrypted data. The keys to decrypt messages live on your device and your contact's device only. We have no technical ability to read your messages.
Are files and media also encrypted?
Yes. All file and media transfers within Zitto conversations are subject to the same end-to-end encryption as text messages.
