Client-side encryption is a security method where files are encrypted on the user’s device before being uploaded to the cloud or transmitted over a network. Unlike server-side encryption, where the service provider manages encryption keys, client-side encryption ensures that only the user has control over their decryption key, enhancing privacy and security.

A common use case for client-side encryption is protecting sensitive personal and business data in cloud storage. Since the encryption happens before the file leaves the device, even if a cloud provider’s servers are breached, the data remains unreadable without the user’s decryption key.

This encryption model is particularly valuable for privacy-focused users, businesses handling confidential information, and compliance with data protection regulations like GDPR. It ensures zero-knowledge security, meaning even the storage provider cannot access the contents of encrypted files.