TextArray
100% local

Encrypt text with a password

Encrypt text with a password using AES — only someone who knows it can read it back.

Input
Output
Related tools
ROT13 / Caesar cipherEncoding & conversionHash generatorDeveloper toolsPassword generatorRandom generatorsBase64 encode and decodeEncoding & conversion
Encrypt text with a password
Encrypting text with a password turns a readable message into a block of Base64 that only someone holding the password can read back. Reach for it before pasting an API key into a ticket, sending a colleague a set of credentials, keeping private notes in a synced folder, or writing a journal in a plain text file that other people on the machine can open.
Pick a mode and type a password. In encrypt mode the tool takes your text and returns the encrypted block, ready to copy wherever it needs to go. In decrypt mode you paste that block back, enter the same password, and the original text reappears. The password field is masked and, unlike every other option on this site, it is deliberately never written to your browser's storage.
The work is done by AES-256-GCM through the browser's native Web Crypto API. Your password is stretched into a key with PBKDF2-HMAC-SHA256 over 210,000 iterations using a random 16-byte salt, and every message gets a fresh random 12-byte initialisation vector. The salt and IV travel inside the output, which is why encrypting the same sentence twice gives two different blocks. GCM also authenticates the data, so a block that was edited or truncated on the way fails to decrypt instead of quietly returning garbage.
All of it happens on your device: no password, no key and no plaintext is ever sent anywhere, which is the only reason a tool like this deserves your trust. That cuts both ways, though — there is no recovery and no back door. Lose the password and the text is gone permanently, so save it in a password manager before you close the tab.
FAQ
What happens if I forget the password?
The text is unrecoverable. There is no reset, no hint and no back door — the key exists only for as long as you are typing the password. Store it in a password manager before you close the tab.
Which algorithm does it use?
AES-256-GCM via the browser's Web Crypto API, with the key derived from your password by PBKDF2-HMAC-SHA256 over 210,000 iterations. A random salt and initialisation vector are generated per message and packed into the output.
Why does the same text encrypt to something different every time?
Each run uses a fresh random salt and IV, so identical text produces a different block. That is intentional: it stops anyone from spotting that two messages are the same. Every block still decrypts with the same password.
How strong is this in practice?
The algorithm is standard and sound, so the weak point is the password. A short or reused one can be guessed offline no matter how good the cipher is. Use a long passphrase or generate one with the password generator.
Is my text or password uploaded anywhere?
No. Encryption and decryption run entirely in your browser, and the password is never sent anywhere or saved to storage. That is what makes it safe to encrypt something genuinely sensitive here.