Text Encryptor
Encrypt and decrypt text with custom password
La misma contraseña se necesita para descifrar el texto.
Cifrado seguro
Este cifrador utiliza AES-GCM con una clave derivada de tu contraseña mediante PBKDF2. El resultado incluye el IV y el salt necesarios para el descifrado. Todo el procesamiento ocurre en tu navegador.
Online AES-256 Text Encryptor - Encrypt and Decrypt Messages
What is AES-256 and why is it the world encryption standard?
AES (Advanced Encryption Standard) with a 256-bit key is the most secure widely available symmetric cipher. Adopted by the United States government in 2001 after a public competition, AES-256 offers 2^256 possible keys, a number so vast that every computer on Earth working together could not exhaust it within the age of the universe. It is the encryption used by intelligence agencies, banks and military systems. This tool implements AES-256-GCM (Galois/Counter Mode), which on top of encryption provides authentication: it detects whether the ciphertext has been tampered with.
How password-based encryption works with PBKDF2
When you type a password it is not used directly as the encryption key. It first goes through PBKDF2 (Password-Based Key Derivation Function 2), which combines it with a random salt and runs thousands of hash iterations. That turns simple passwords into robust cryptographic keys and makes dictionary attacks extremely slow. The salt guarantees that the same password produces a different key every time. The output bundles the salt, the initialisation vector and the authentication tag in Base64, so later decryption needs nothing but the password.
Use cases for text encryption
This tool fits several scenarios: sending sensitive information over insecure channels such as email or chat when the recipient already knows the agreed password; storing confidential notes in cloud services that offer no end-to-end encryption; keeping passwords or secrets inside text files; sharing temporary credentials with colleagues; and protecting personal data in backups. Remember that the security rests on the strength of your password and on sharing it through a different channel from the encrypted message itself.
If you work with this tool, you will probably also find these useful Base64 Encoder, AES Encryption, RSA Key Generator, HMAC Generator.
Frequently asked questions
Is it safe to encrypt sensitive data in the browser?
Yes. This tool uses the native Web Crypto API, which implements AES-256-GCM securely. All processing happens locally and your data never leaves your device. For extremely sensitive material, however, consider dedicated encryption software such as VeraCrypt, GPG or an audited application built for your specific use case.
How long should my encryption password be?
A minimum of 12 characters, ideally 16 or more, mixing uppercase, lowercase, digits and symbols. Better still, use a passphrase of four or five random words. PBKDF2 strengthens weak passwords, but a strong password remains fundamental. Avoid personal information and single dictionary words.
Can I decrypt if I forget the password?
No. AES-256 encryption is irreversible without the correct password. There is no backdoor, no recovery and no secret question. If you lose the password the data is permanently inaccessible. That is a security feature rather than a bug, so keep your encryption passwords in a password manager.
Why is the encrypted text so long?
The output contains a 16-byte salt, a 12-byte IV, a 16-byte authentication tag and the ciphertext itself, all encoded in Base64, which expands the size by roughly 33%. Every one of those components is needed for security: the salt defeats rainbow tables, the IV guarantees that encrypting the same text twice yields different results, and the tag verifies integrity.