Free AES Text Encrypt & Decrypt Online — Encrypt Text with a Password

Encrypt text with military-grade AES-256 using just a passphrase — or decrypt it back. PBKDF2 key derivation, random salt and IV, all on your device.

Free AES Text Encrypt & Decrypt Online — Encrypt Text with a Password | syedwaleed.com
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Free AES Text Encrypt & Decrypt

Encrypt text with a passphrase using AES-256-GCM — or decrypt it back. Everything runs in your browser; your passphrase never leaves the device.

Use a passphrase only you know. Lose it, and nobody — not even this page — can recover your text.

Format: Base64 of (salt 16 bytes + IV 12 bytes + ciphertext). A fresh random salt and IV are generated for every encryption.

100% private

Encryption happens on your device with the Web Crypto API. Nothing is uploaded anywhere.

No signup

No account, no email, no waiting — encrypt instantly.

Free forever

No limits on text length or number of encryptions.

How to use the AES Encrypt & Decrypt tool

  1. 1Enter your text and passphrase

    On the Encrypt tab, paste or type the text you want to protect and choose a strong passphrase.

  2. 2Encrypt and copy

    Hit Encrypt text. Your AES-256-GCM ciphertext appears as Base64 — copy it or download it as a .txt file.

  3. 3Decrypt it back anytime

    On the Decrypt tab, paste the ciphertext and the same passphrase to recover the original text.

Features

AES-256-GCM encryption

Military-grade authenticated encryption via your browser’s native Web Crypto API.

PBKDF2 key derivation

Your passphrase is stretched with 250,000 PBKDF2-SHA-256 iterations plus a random salt.

Fresh salt and IV every time

Each encryption uses a new random salt and IV, so identical text never produces identical output.

Clear wrong-passphrase errors

GCM authentication detects a wrong passphrase or tampered ciphertext and tells you plainly.

Copy and download

Send results to your clipboard in one click or download the ciphertext as a .txt file.

Works offline after load

All crypto runs locally — the page needs no server round trips once it’s open.

Frequently asked questions

Does my passphrase or text leave my device?
No. Everything runs in your browser using the Web Crypto API. Your passphrase, plaintext, and ciphertext are never uploaded, logged, or stored — close the tab and they’re gone.
What happens if I forget my passphrase?
Your text cannot be recovered. There is no backdoor and no reset option — that’s the point of real encryption. Keep your passphrase somewhere safe.
Why does the same text encrypt differently each time?
A new random salt and IV are generated for every encryption. This is by design: it means an attacker can’t tell whether two ciphertexts hide the same message.
What does “wrong passphrase” mean during decryption?
The decryption uses AES-GCM, an authenticated cipher. If the passphrase is wrong — or the ciphertext was altered — the authentication check fails and the tool reports a clear error instead of showing garbled text.
What format is the encrypted output?
Base64 text containing the 16-byte salt, the 12-byte IV, and the ciphertext concatenated together. It pastes into the Decrypt tab as-is.
Is this suitable for real secrets?
AES-256-GCM with 250,000 PBKDF2 iterations is solid cryptography, but only if your passphrase is strong and kept private. For highly sensitive data, combine good operational habits with this tool.
Is this tool free?
Yes. Unlimited encryptions and decryptions, no signup, no limits.
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