AES Text Encryption

AES Text Encryption is a free browser-based tool that encrypts and decrypts text with a passphrase using AES-GCM 256-bit encryption. You paste in a message, choose a passphrase, and get back a Base64 blob that only someone with the same passphrase can unlock — all computed locally with the Web Crypto API, so nothing is ever uploaded.

What does this AES encryption tool do?

It turns readable text into an unreadable, authenticated ciphertext and back again. Under the hood it uses AES in Galois/Counter Mode (AES-GCM) with a 256-bit key. Your passphrase is not used directly as the key; instead it is stretched with PBKDF2 (250,000 SHA-256 iterations) and a random salt, which makes brute-forcing weak passphrases far slower. A fresh random initialization vector (IV) is used every time, so encrypting the same text twice never yields the same output.

How to encrypt and decrypt text

1. Open the Encrypt tab and paste or type the text you want to protect.
2. Enter a strong passphrase. Use the show/hide toggle to confirm you typed it correctly.
3. Click Encrypt Text and copy the Base64 output that appears.
4. Send that Base64 blob to your recipient over any channel — email, chat, a note.
5. To read it, switch to the Decrypt tab, paste the blob, enter the same passphrase, and click Decrypt Text.

Why use client-side AES encryption?

Because privacy should not depend on trusting a server. Everything here runs in your own tab, which means your message and passphrase never travel across the network. That makes it a good fit for sharing secrets, notes, credentials, or short sensitive files as text. If you need a passphrase worth trusting, generate one first with the Strong Password Generator, then reuse it here.

• Authenticated encryption: AES-GCM detects any tampering, so a modified ciphertext simply fails to decrypt.
• Key stretching: PBKDF2 with a random salt defends against dictionary attacks on your passphrase.
• Random IV per message: identical inputs produce different outputs, hiding repetition.
• Portable output: the salt, IV, and ciphertext are packed into a single Base64 string.
• Zero dependencies: only the native crypto.subtle API is used — no third-party libraries.

What is the Base64 output?

Encryption produces raw binary bytes, which are awkward to copy and paste. The tool concatenates the random salt, the IV, and the ciphertext, then encodes the whole thing as Base64 text so it survives being pasted anywhere. If you are curious about that encoding on its own, the Base64 Encode and Decode tool shows exactly how binary maps to safe ASCII characters. During decryption the tool reverses the process: it Base64-decodes the blob, slices off the salt and IV, re-derives the key from your passphrase, and verifies the authentication tag before revealing the plaintext.

Encryption versus hashing: when to use which

Encryption is reversible with the right key, which is what you want for messages you need to read again. Hashing is a one-way fingerprint and cannot be undone — it is for verifying integrity, not hiding recoverable content. If your goal is to confirm a file has not changed, a checksum from the SHA-256 Hash Generator is the right tool, and the older MD5 Hash Generator is still handy for quick non-security checksums. When you need to prove a message came from someone who holds a shared secret, an authentication code from the HMAC Generator is the appropriate choice. Reach for this AES tool only when you actually need to get the original text back.

Frequently Asked Questions

Is my text or passphrase sent to a server?

No. All encryption and decryption happen entirely inside your browser using the Web Crypto API. No text, passphrase, or derived key is transmitted, logged, or stored anywhere.

Can I recover my data if I forget the passphrase?

No. There is no backdoor, reset link, or recovery option. The key is derived from your passphrase, so if you lose it the ciphertext is permanently unreadable. Store your passphrase somewhere safe.

What encryption algorithm is used?

AES-GCM with a 256-bit key. The key is derived from your passphrase using PBKDF2 with SHA-256 and 250,000 iterations plus a random 16-byte salt, and each message uses a fresh random 12-byte IV.

Why does encrypting the same text give different results each time?

Because a new random salt and IV are generated for every encryption. This is intentional and secure — it prevents attackers from spotting that two ciphertexts contain the same message.

Can the recipient decrypt without this exact tool?

Any implementation that reads the same format — salt, then IV, then AES-GCM ciphertext, Base64-encoded, with matching PBKDF2 parameters — can decrypt it. In practice the simplest path is to have them use this same page and passphrase.

Is this strong enough for real security?

AES-GCM 256-bit with PBKDF2 is a widely trusted, modern standard. The real weak point is passphrase strength, so choose a long, random passphrase and share it through a separate, trusted channel.