A wrong password fails cleanly, not silently

Older encryption tools using AES-CBC will happily decrypt a file with the wrong password and produce complete garbage — a PDF that crashes, a ZIP that won't open, a text file of gibberish. You won't know it failed until you open the output and waste time diagnosing corrupted data. AES-256-GCM changes this: the cipher includes a 16-byte authentication tag that proves both the key and the ciphertext are valid. If either is wrong, decryption fails with an explicit error before writing anything.

This tool requires your password. It is not a password recovery tool.

If you've lost the password, the file cannot be opened — there is no backdoor, no reset link, and no practical way past the PBKDF2 key derivation (200,000 iterations, SHA-256). All work happens in your browser; the file never leaves your device. To decrypt a file, you must have the exact password that was used to encrypt it.

Format lock: only this tool can read its own .enc files

The .enc container uses a 4-byte magic header (7BB1) plus a random salt and IV. Files encrypted here are locked to this format — they won't open in other tools even with the correct password, and files from other tools won't open here. This is by design: the format is simple, auditable, and forward-compatible (the magic bytes allow the iteration count to increase over time without breaking old files).

In-browser processing means your password stays private

The decryption runs entirely in your browser using WebCrypto, the browser's native cryptographic API. No network call is made; no log is kept. Drop a .enc file, enter the password, and the decrypted file is ready to download within seconds. File size is not limited by this tool—only by available memory.

Out of scope

• Password recovery or reset
• Decrypting files from other encryption software
• Batch decryption of thousands of files (the browser will run out of memory)
• Recovering corrupted .enc files with damaged headers

For pasted ciphertext rather than files, use the Text Decrypter, which shares this format. To open password-protected archives, use Remove ZIP Password.