With Transfer-Encoding: chunked each piece is a hex size, CRLF, the data and CRLF. A chunk of size 0 ends the body.
Chunked encoding
An HTTP/1.1 way to send a body in pieces without knowing its total length.
With Transfer-Encoding: chunked each piece is a hex size, CRLF, the data and CRLF. A chunk of size 0 ends the body.