Caesar Cipher & ROT13 Decoder
Classical ciphers and encodings — shift, rotate, encode, decode
These are puzzle ciphers, not protection. Every method here is reversible by anyone who recognises it, and that is what they are for — crosswords, CTFs, obfuscating a spoiler. To actually keep something private, use our AES-256 text encryption tool instead.
XOR (repeating key): A repeating-key XOR, the byte version of a Vigenère cipher. Fine for puzzles, and breakable without your key. For anything real, use the encrypt text tool.
Free Online Text Encryption & Decryption Tool
Encryption is the process of converting readable text into an unreadable format so that only someone with the right key or method can read it. It has been used for thousands of years — from Caesar\u2019s military messages to modern-day HTTPS connections. Whether you need to protect a message, learn how ciphers work, or encode data for storage, this tool has you covered.
This free Text Encrypt & Decrypt tool supports seven different methods. Choose a cipher, type or paste your text, and click Encrypt or Decrypt. Methods that require a key — the repeating-key XOR and the Caesar shift — let you set the key directly in the toolbar. Methods like ROT13, Base64, Reverse, Hex Encode, and Morse Code work without a key.
The Swap button moves your output back to the input field and switches the mode, so you can encrypt and then decrypt in seconds. Copy the result to your clipboard or clear everything and start over. All processing runs in your browser. No data is sent to any server. No account required.
Supported Encryption Methods
XOR (repeating key)
A repeating-key XOR encoded in Base64. Requires a secret key. Both parties must know the key to decrypt the message.
Caesar Cipher
One of the oldest ciphers. Each letter is shifted by a fixed number of positions. The key is the shift amount (default 3). Easy to break but great for learning.
ROT13
A special case of the Caesar cipher that shifts letters by 13. Since the alphabet has 26 letters, applying ROT13 twice returns the original text.
Base64 Encoding
Converts binary data to a text format using 64 printable characters. Not encryption — it is encoding. Commonly used in emails, data URIs, and APIs.
Hex Encoding
Converts each character to its hexadecimal (base-16) representation. Often used in programming, colour codes, and debugging network data.
Morse Code
Converts letters and numbers to dots and dashes. Originally developed for telegraph communication. Space between words is represented by a slash (/).