Are you saying that is the to string value of a URL object instantiated with the url of a page containing just an image tag, or are you saying it’s the value when you instantiate an object with a url parameter to the png file itself? If it’s the png file itself my 0.02 is that is a logical choice. Obviously the to string ( or whatever it is, I’m not a JS dev ) isn’t the binary data, and I believe in the binary encoded response body there is a meta data signature block that contains that info.