How to Encrypt Text with a Password (AES-256)

To encrypt text with a password, type or paste it into the ByteTools AES Text Encrypter, enter a strong password, and click Encrypt — you get a single Base64 blob protected with AES-256-GCM that you can store or share. A fresh random salt and IV are generated for every message and packed into the output, so there is nothing extra to track. This guide covers each step and what happens behind the scenes.

What the tool produces

The encrypter takes your plain text and a password and returns one self-contained Base64 string. Inside that string are three parts bundled together: the random salt, the initialisation vector (IV) and the AES-GCM ciphertext. Because everything decryption needs is embedded, you can paste the blob into a note, a message or a file and recover it later with just the password.

Step-by-step encryption

1. Enter your text. Type or paste the message you want to protect into the input box.
2. Choose a strong password. Pick something long and memorable, or generate one and store it safely — this password is the only key to your text.
3. Click Encrypt. The tool stretches your password into a 256-bit key with PBKDF2 (SHA-256, 200,000 iterations) using a random salt, then encrypts with AES-GCM and a random IV.
4. Copy the Base64 blob. The single output string already contains the salt and IV — copy it as one piece.
5. Store or share it. Save the blob wherever you like, and decrypt it later with the matching AES Decrypt Text tool and the same password.

What each security piece does

Component	Purpose
PBKDF2	Stretches your password into a strong 256-bit key, slowing brute-force attempts
Random salt	Ensures the same password produces a different key each time
Random IV	Makes identical messages encrypt to different ciphertext
AES-256-GCM	Encrypts the text and adds a tamper-detecting authentication tag

Because GCM is authenticated encryption, the blob also carries a tag that lets the decrypter detect a wrong password or altered ciphertext, failing cleanly rather than returning garbage.

Why encrypting in the browser is private

All encryption runs locally with the Web Crypto API. Your plaintext and password never leave the page, are not logged, and the tool works offline. That makes it genuinely safe for sensitive text — the only copy of your secret in readable form stays on your device. One caveat: because there is no backdoor, if you lose the password the ciphertext cannot be recovered, so store the password carefully.

Try the AES Text Encrypter — free and 100% in your browser.

FAQ

How long should my password be?

Longer is stronger. A passphrase of several unrelated words is both hard to guess and easy to remember. PBKDF2 stretching adds resistance to brute force, but the password itself is still the foundation of your security.

Where can I decrypt the blob later?

Use the matching ByteTools AES Decrypt Text tool with the same password. Both tools share the identical salt-IV-ciphertext format, so a blob made here decrypts correctly there.

Do I need to save the salt and IV separately?

No. They are embedded inside the Base64 blob, so the single output string is all you need to keep. Just record the password separately.

Is it safe to encrypt very sensitive text?

Yes. Encryption happens entirely on your device with a standard, well-vetted algorithm, and nothing is uploaded. For extra assurance you can disconnect from the network — the tool still works offline.

Related free tools

• AES Text Decrypter — recover the text from your blob.
• Secure Token Generator — generate strong random secrets.
• HMAC Generator — authenticate messages with a keyed hash.
• SHA-256 Hash Generator — fingerprint data for integrity checks.

Built by ByteVancer

ByteTools is a free product of ByteVancer, a software and web development studio building web apps, SaaS and custom software. If you need secure, thoughtfully built software, explore what ByteVancer can create for you.