🔒 Text Encryption Tool

About the Text Encryption Tool

This tool encrypts and decrypts text using AES-GCM (a modern authenticated cipher) with a key derived from your password via PBKDF2 with SHA-256 and 100,000 iterations. Everything runs in your browser through the native window.crypto.subtle API — no text or password is ever sent to a server.

How the encrypted output is structured

Each encrypted result is a single Base64 string that bundles everything needed to decrypt (except the password):

• Salt (16 bytes) — random per encryption, used to derive the key from your password.
• IV (12 bytes) — random per encryption, required by AES-GCM and never reused.
• Ciphertext + auth tag — the encrypted bytes plus the GCM authentication tag.

To decrypt, paste the Base64 string back, enter the same password, and the tool will split out the salt and IV, re-derive the key, and verify the auth tag. If the password is wrong (or the data was tampered with), decryption fails safely.

How to use it

1. Choose Encrypt or Decrypt from the mode dropdown.
2. Type a password — the same password must be used to decrypt later.
3. Paste your text into the text box.
4. Press the action button. The result appears below; copy it with one click.

Frequently asked questions

Can the password be recovered if I forget it? No. The key is derived from your password locally; there is no recovery mechanism and no server that knows it. Keep your password safe.

Is this as secure as a dedicated app? The cryptographic primitives are the same ones browsers use for TLS, so the math is sound. The main risk is a weak password — use a long passphrase.

Why does decryption fail sometimes? The most common cause is a wrong password. It can also fail if the Base64 string was truncated, mangled by an editor, or if the text was encrypted with a different tool.

Is anything uploaded? No. The crypto runs entirely in JavaScript on your device.