Let's encode and decode content using Burp Suite Decoder:

1. To pass a given value to Burp Suite Decoder, highlight the desired string, right-click on it, and then select Send to Decoder. In the example provided, the value of the Cookie parameter is sent to the decoder, as shown in the following screenshot:

2. By clicking on the Smart decode button, Burp Suite automatically identifies the encoding as URL encoding and decodes it in the field below where the encoded text was originally entered, as shown in the following screenshot:

3. If Burp Suite is unable to determine the type of encoding used, manual decoding can be performed for multiple different types of encoding to include URL, HTML, Base64, ASCII hex, and so on. A decoder can also be used to encode strings that are entered using the Encode as... function.