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Specification of the message pack format can be found here: ''

There are libraries written in the most common languages. You can download libraries from the official site: ''

The following table provides information on how different types of data are encoded in the message pack.

format namefirst byte (in binary)first byte (in hex)
positive fixin0xxxxxxx0x00 - 0x7f
fixmap1000xxxx0x80 - 0x8f
fixarray1001xxxx0x90 - 0x9f
fixstr101xxxxx0xa0 - 0xbf
(never used)110000010xc1
bin 8110001000xc4
bin 16110001010xc5
bin 32110001100xc6
ext 8110001110xc7
ext 16110010000xc8
ext 32110010010xc9
float 32110010100xca
float 64110010110xcb
uint 8110011000xcc
uint 16110011010xcd
uint 32110011100xce
uint 64110011110xcf
int 8110100000xd0
int 16110100010xd1
int 32110100100xd2
int 64110100110xd3
fixext 1110101000xd4
fixext 2110101010xd5
fixext 4110101100xd6
fixext 8110101110xd7
fixext 16110110000xd8
str 8110110010xd9
str 16110110100xda
str 32110110110xdb
array 16110111000xdc
array 32110111010xdd
map 16110111100xde
map 32110111110xdf
negative fixint111xxxxx0xe0 - 0xff