Text Encryption Tool: Encrypt and Decrypt Easily

Do you need to transmit sensitive information or decode encrypted messages quickly? Our online text encryption tool allows you to encrypt and decrypt your data instantly using popular algorithms such as Caesar, Vigenère, Morse, or Base64. Completely free and 100% client-side, this service ensures total privacy: no text is ever sent to a server, as all processing happens locally within your browser. Use our intuitive interface to encrypt your messages securely with no installation required.

Algorithm

Mode

Shift (1-25)

Plain text

Encrypted text

History

No encryption yet.

How does text encryption work?

Encryption transforms readable text (plaintext) into unreadable text (ciphertext) using an algorithm and a key. Decryption is the reverse operation. The algorithms shown here are classical ciphers for educational purposes — they are not secure for professional use (use AES or ChaCha20 for sensitive data).

Caesar cipher and ROT13

The Caesar cipher shifts each letter of the alphabet by a fixed number of positions (the key). With a key of 3, A→D, B→E, etc. It is one of the oldest known algorithms, used by Julius Caesar for military communications. ROT13 is a special case with a shift of 13 — applying ROT13 twice returns the original text.

Vigenère cipher

The Vigenère cipher uses a keyword to apply multiple Caesar shifts cyclically. With key "KEY", the 1st letter is shifted by 10 (K), the 2nd by 4 (E), the 3rd by 24 (Y), then repeats. It is much more robust than Caesar because the same letter can be encrypted differently depending on its position.

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