End-to-end encrypted chats between you and one other person have their own security code used to verify that the calls and the messages you send to that chat are end-to-end encrypted. This code can be found in the contact info screen, both as a QR code and a 60-digit number. These codes are unique to each individual chat and can be compared between people in each chat to verify that the messages you send to the chat are end-to-end encrypted. Security codes are just visible versions of the special keys shared between you - and don't worry, it's not the actual keys themselves, which are always kept secret.

At times, the security codes used in end-to-end encrypted chats between you and one other person might change. This is likely because you or your contact reinstalled WhatsApp, changed phones, or added or removed a paired device. You can always verify that a contact's security code is legitimate. Learn how in this article on end-to-end encryption.

Receive notifications when security codes change

You can enable security notifications to receive notifications when your security code changes for a contact’s phone in an end-to-end encrypted chat. You’ll need to enable the setting on each device where you want to get notifications.

Enable security code notifications

Android

1. Open WhatsApp > tap More options > Settings.
2. Tap Account > Security.
3. Turn on Show security notifications on this phone.

iPhone

1. Go to WhatsApp Settings.
2. Tap Account > Security.
3. Turn on Show Security Notifications on This Phone.

Web and Desktop

1. Open WhatsApp > click Menu or above your chats list > Settings.
2. Click Security.
3. Turn on Show security notifications on this computer.

Disable security code notifications

Android

1. Open WhatsApp > tap More options > Settings.
2. Tap Account > Security.
3. Turn off Show security notifications on this phone.

iPhone

1. Go to WhatsApp Settings.
2. Tap Account > Security.
3. Turn off Show Security Notifications on This Phone.

Web and Desktop

1. Open WhatsApp > click Menu or above your chats list > Settings.
2. Click Security.
3. Turn off Show security notifications on this computer.