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Encrypt Files with AES-GCM — Password-Protected

Drop any file (or a folder) onto MiniMax Converter's File encrypt tool, choose a password, get back a .mmcenc file that's indistinguishable from random bytes without the password. AES-256-GCM under the hood — authenticated encryption, so tampering is detectable. Decryption is the same tool in reverse.

Encrypt Files with AES-GCM — Password-Protected — screenshot

How it works

AES-256 in GCM mode (Galois/Counter Mode). The password is stretched into a 256-bit encryption key via Argon2id (memory-hard KDF — slow to brute-force). A random 12-byte nonce per file ensures the same plaintext + password produce different ciphertext. The 16-byte GCM authentication tag at the end of the file lets the decryptor verify nothing was tampered with.

How to use it

  1. Open Tools → Security & Cryptography → File encrypt / decrypt.
  2. Drop the file (or folder) you want to encrypt.
  3. Enter a password — pick a strong one, the password is the ONLY way to decrypt (no key escrow, no backdoor).
  4. Output is written as {original}.mmcenc. The original is preserved unless you tick "Delete original".
  5. To decrypt: drop the .mmcenc file onto the same tool and enter the password.

The .mmcenc format

Self-describing container: 4-byte magic + version + Argon2 parameters + nonce + ciphertext + auth tag. Cross-platform — encrypt on Linux, decrypt on Windows or macOS with the same password. Documented in the source for anyone who wants to write a third-party decryptor.

Questions and answers

Is AES-256-GCM secure?

It's the modern standard for authenticated symmetric encryption. Used everywhere from TLS 1.3 to disk encryption to messaging apps. No known practical attacks.

What happens if I forget the password?

The file is unrecoverable. No backdoor, no master key, no "forgot password" link. Pick a password you can remember (or store in a password manager) before encrypting anything important.

Can I encrypt a whole folder?

Yes — drop the folder. The tool encrypts each file individually (so partial-decrypt is possible if you only need one file back).

How does this compare to 7-Zip with a password?

7-Zip with AES-256 is also secure, but the container is older and uses a weaker KDF by default. .mmcenc uses Argon2id which is purpose-built to resist GPU/ASIC brute-forcing.

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