Base64 Encoding/Decoding Type in the message you want to encode in Base64, or paste Base64 encoded text into the text field, select Encode or Decode, and click the button! You can use Base64 encoded messages with the Steganography page. onClick="document.base64Form.theText.value=encode64(document.base64Form.theText.value);"> onClick="document.base64Form.theText.value=decode64(document.base64Form.theText.value);">