QR code pairing is a secure method used to link devices or applications to a user account by scanning a unique QR code. When setting up a new device or app, the user scans a QR code displayed on another device or screen. This code contains encrypted information that authenticates the pairing request, ensuring that only authorized devices can connect. QR code pairing is commonly used in multi-factor authentication, secure messaging apps, and IoT device onboarding. It enhances security by reducing manual entry errors and minimizing the risk of credential theft, as the sensitive data is transmitted securely through the code.