The quoted printable encoding was designed for e-mail, but it works surprisingly well in XML. It can encode any ASCII or UTF-8 text including characters that are not normally allowed in XML documents, such as form feed, vertical tab, null, and the reserved XML characters less than sign (<), greater than sign (>), and ampersand (&). Most importantly, most of the ASCII text is intact and can be read by a normal browser. Only the problematic characters need to be escaped.
The basic algorithm uses just five rules.
Each byte can be encoded as an equals sign (=) followed by two hexadecimal digits; for example, a less than sign can be represented as =3C. Only capital letters are used for the hexadecimal digits A–F.
The bytes with values ...