End-to-end encryption (E2EE) is a communication method where messages are encrypted on the sender's device and can only be decrypted on the recipient's device. No intermediate server - not even the messaging platform's own servers - can read the content.

How E2EE Works

  1. Each user has a public key (shareable) and a private key (stored only on their device).
  2. When Alice sends a message to Bob, it is encrypted with Bob's public key.
  3. Only Bob's private key can decrypt it. The message travels through servers as encrypted ciphertext.
  4. Even if the service's servers are hacked or served a legal order, the encrypted messages are unreadable without the private keys.

Apps With True E2EE

AppE2EE by DefaultProtocol
SignalYes (all messages)Signal Protocol
WhatsAppYesSignal Protocol
iMessageYes (between Apple devices)Apple's protocol
TelegramOnly in "Secret Chats"MTProto
Standard SMSNoNone
Regular emailNo (unless PGP used)SMTP (unencrypted by default)

Does E2EE Protect Metadata?

E2EE protects message content, not metadata. The service can still see who is messaging whom, when, and how frequently. Signal minimizes metadata collection; most other apps do not.

People Also Ask

Why would someone use end-to-end encryption?
To ensure private conversations remain private from the service provider, hackers who breach servers, and government requests for data. It is the standard for secure personal and professional communication.
Is it good to turn on end-to-end encryption?
Yes. For apps that offer it as an option (Telegram's Secret Chat mode), enabling it is always better for privacy. Signal and WhatsApp are E2EE by default - nothing to enable.

Related: VPN encryption | SSL/TLS