Facebook testing end-to-end encryption in Messenger, branded Secret Conversations

Facebook Messenger is the latest app to adopt end-to-end encryption for its chats, ensuring that conversations cannot be accessed even by Facebook. It’s just in testing so far, but the company says that it will be made available more widely in the course of the summer.

We are starting to test the ability to create one-to-one secret conversations in Messenger that will be end-to-end encrypted and which can only be read on one device of the person you’re communicating with. That means the messages are intended just for you and the other person — not anyone else, including us.

While Apple uses end-to-end encryption as standard for both iMessages and FaceTime, and WhatsApp followed suit in April, Facebook is taking a slightly different approach …

Instead of automatically using end-to-end encryption for all messages, Facebook says it will be an option which people can choose to activate on a chat-by-chat basis. The option is known as Secret Conversations.

Starting a secret conversation with someone is optional. That’s because many people want Messenger to work when you switch between devices, such as a tablet, desktop computer or phone. Secret conversations can only be read on one device and we recognize that experience may not be right for everyone. It’s also important to note that in secret conversations we don’t currently support rich content like GIFs and videos, making payments, or other popular Messenger features.

Facebook has published a white paper outlining the approach it has taken. Images included in secret conversations are also encrypted, but metadata is not.

The company added SMS support to its Android messaging app last month.