The CryptoJS URL (https://code.google.com/p/crypto-js/) contains a collection of secure cryptographic algorithms written in Javascript. encode, pass in the control var ckey = $("#cryptonkey").val(); var y=document.getElementById(control).value; var encrypted = CryptoJS.AES.encrypt(y, ckey); document.getElementById("crypton").value=encrypted; decode, pass in the control var ckey = $("#cryptonkey").val(); var y=document.getElementById(control).value; var decrypted = CryptoJS.AES.decrypt(y, ckey); decrypted = decrypted.toString(CryptoJS.enc.Utf8); document.getElementById("cryptoff").value=decrypted; If you receive a secret message and know the secret key, you can enter the secret key and place your secret message into the "crypt-on" box. The secret message will be visible to you in the "crypt-off" box.