Security & Crypto Tools
AES Encrypt / Decrypt
Encrypt and decrypt text with AES-256-GCM using a passphrase.
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What is AES?
A passphrase-based AES tool: PBKDF2 stretches the passphrase into a 256-bit key, GCM authenticates the ciphertext, and an IV ensures unique output.
How it works
Web Crypto derives the key with 100k PBKDF2 iterations and encrypts with AES-GCM; decryption takes the hex ciphertext + IV and your passphrase.
- Enter your input. Type or paste your input into the field above — the tool responds instantly.
- Review the result. Output updates live as you type. Everything runs entirely in your browser.
- Copy or download. Use the Copy button to grab the result, or Download to save it as a file.
Examples
Encrypting a message
Encrypt text with AES-256-GCM using a passphrase, or decrypt a ciphertext + IV pair — entirely in the browser.
Common mistakes
Reusing an IV
GCM requires a fresh, unique IV per encryption. Reusing one with the same key leaks information about the plaintexts.
Frequently asked questions
Why does the same input produce different output each time?
GCM uses a fresh random IV per encryption — identical plaintext yields different ciphertext, which is what makes it secure. Keep the IV with the ciphertext to decrypt.