Understanding File Encryption: AES, RSA, and Browser-Based Crypto
A beginner-friendly explainer on file encryption algorithms, how they work, and how to encrypt files securely in your browser.
File encryption transforms your data into an unreadable format that can only be reversed with the correct key. It is the foundation of digital privacy — protecting everything from personal photos to corporate contracts.
The two main encryption families are symmetric (AES) and asymmetric (RSA). AES uses the same key for encryption and decryption, making it fast and ideal for file encryption. RSA uses a key pair (public + private) and is better suited for secure communication.
AES-256-GCM is the current gold standard for file encryption. The "256" refers to the key length in bits, making brute-force attacks computationally impossible. GCM mode adds authentication, detecting any tampering with the encrypted data.
Modern browsers include the Web Crypto API, which provides hardware-accelerated cryptographic operations. This means you can encrypt and decrypt files directly in your browser at near-native speed — no software installation needed.
ConvertCraft's File Encrypt tool leverages the Web Crypto API to perform AES-256-GCM encryption entirely client-side. Enter a password, drop your file, and receive an encrypted output that only you can decrypt. Your original file never leaves your device.