PHP code utilized to encode/decode:$str = $_POST["encode"];echo base64_encode($str); $str = $_POST["decode"];echo base64_decode($str); base64: Base 64 literally means a positional numbering system using a base of 64. It is the largest power of two base that can be represented using only printable ASCII characters. This has led to its use as a transfer encoding for email among other things. All well-known variants of base 64 use the characters A–Z, a–z, and 0–9 in that order for the first 62 digits but the symbols chosen for the last two digits vary considerably between different systems that use base 64. In MIME, e-mail base64 is a data encoding scheme whereby an arbitary sequence of bytes is converted to a sequence of printable ASCII characters. It is defined as a MIME content transfer encoding for use in internet e-mail. The only characters used are the upper- and lower-case Roman alphabet characters (A–Z, a–z), the numerals (0–9), and the "+" and "/" symbols, with the "=" symbol as a special suffix code. Full specifications for this form of base64 are contained in RFC 1421 and RFC 2045. The scheme is defined to encode a sequence of octets (bytes). This matches up with the definition of files on almost all systems. The resultant base64-encoded data has a length that is greater than the original length by the ratio 4:3, and typically appears as seemingly random characters.
