Base64 - text format of binary data
Base64 is an encoding system that converts binary data to a text string, which contains only the basic
ASCII characters.
It is used, for example, in the
MIME extension for transmission e-mails in the original 7-bit mail system on the Internet.
It is defined in
RFC 4648.
Base64 always encodes three octets of binary data using four
ASCII characters.
The encoding uses a 64-element character set consisting of upper and lower case letters of the English alphabet, digits and plus ('+') and slash ('/') characters.
If the number of octets of the original data is not divisible by three, then adds one or two equals signs ('=') to the end of the encoded text.
- The length of the resulting string is usually increased by 33%.
- The
Base64 encoding is shorter than the
HexaString encoding, which uses only
0-9, A-F characters for encoding and which increases the length by 50%.