SECURITY TOOL
File Encryption / Decryption
Encrypt or decrypt any file with a passphrase, using AES-256-GCM.
About this tool
Encrypt any file with a passphrase using AES-256-GCM, entirely in your browser — the file is never uploaded anywhere. Download the resulting encrypted file, then use "Decrypt" with the same passphrase later to recover the original, exact byte-for-byte and with its original filename restored.
Frequently asked questions
- Is my file ever uploaded to a server?
- No — reading, encrypting, and decrypting all happen locally using the Web Crypto API. Nothing about the file or passphrase ever leaves your device.
- What happens if I forget the passphrase?
- The file cannot be recovered. There is no backdoor, password reset, or recovery mechanism — the passphrase is the only key, exactly as with real AES encryption.
- What algorithm is used?
- AES-256-GCM for encryption (which also verifies integrity), with the encryption key derived from your passphrase using PBKDF2 (250,000 iterations, SHA-256) and a random salt generated per file.