CBOR Header Bytes

This table shows all possible CBOR header byte values and their meanings.

	`_0`	`_1`	`_2`	`_3`	`_4`	`_5`	`_6`	`_7`	`_8`	`_9`	`_a`	`_b`	`_c`	`_d`	`_e`	`_f`
`0_`	`0`	`1`	`2`	`3`	`4`	`5`	`6`	`7`	`8`	`9`	`10`	`11`	`12`	`13`	`14`	`15`
`1_`	`16`	`17`	`18`	`19`	`20`	`21`	`22`	`23`	`int 1+1`	`int 1+2`	`int 1+4`	`int 1+8`
`2_`	`-1`	`-2`	`-3`	`-4`	`-5`	`-6`	`-7`	`-8`	`-9`	`-10`	`-11`	`-12`	`-13`	`-14`	`-15`	`-16`
`3_`	`-17`	`-18`	`-19`	`-20`	`-21`	`-22`	`-23`	`-24`	`neg 1+1`	`neg 1+2`	`neg 1+4`	`neg 1+8`
`4_`	`bstr 0`	`bstr 1`	`bstr 2`	`bstr 3`	`bstr 4`	`bstr 5`	`bstr 6`	`bstr 7`	`bstr 8`	`bstr 9`	`bstr 10`	`bstr 11`	`bstr 12`	`bstr 13`	`bstr 14`	`bstr 15`
`5_`	`bstr 16`	`bstr 17`	`bstr 18`	`bstr 19`	`bstr 20`	`bstr 21`	`bstr 22`	`bstr 23`	`bstr 1+1`	`bstr 1+2`	`bstr 1+4`	`bstr 1+8`				`bstr indef`
`6_`	`str 0`	`str 1`	`str 2`	`str 3`	`str 4`	`str 5`	`str 6`	`str 7`	`str 8`	`str 9`	`str 10`	`str 11`	`str 12`	`str 13`	`str 14`	`str 15`
`7_`	`str 16`	`str 17`	`str 18`	`str 19`	`str 20`	`str 21`	`str 22`	`str 23`	`str 1+1`	`str 1+2`	`str 1+4`	`str 1+8`				`str indef`
`8_`	`arr 0`	`arr 1`	`arr 2`	`arr 3`	`arr 4`	`arr 5`	`arr 6`	`arr 7`	`arr 8`	`arr 9`	`arr 10`	`arr 11`	`arr 12`	`arr 13`	`arr 14`	`arr 15`
`9_`	`arr 16`	`arr 17`	`arr 18`	`arr 19`	`arr 20`	`arr 21`	`arr 22`	`arr 23`	`arr 1+1`	`arr 1+2`	`arr 1+4`	`arr 1+8`				`arr indef`
`a_`	`map 0`	`map 1`	`map 2`	`map 3`	`map 4`	`map 5`	`map 6`	`map 7`	`map 8`	`map 9`	`map 10`	`map 11`	`map 12`	`map 13`	`map 14`	`map 15`
`b_`	`map 16`	`map 17`	`map 18`	`map 19`	`map 20`	`map 21`	`map 22`	`map 23`	`map 1+1`	`map 1+2`	`map 1+4`	`map 1+8`				`map indef`
`c_`	`tag 0`	`tag 1`	`tag 2`	`tag 3`	`tag 4`	`tag 5`	`tag 6`	`tag 7`	`tag 8`	`tag 9`	`tag 10`	`tag 11`	`tag 12`	`tag 13`	`tag 14`	`tag 15`
`d_`	`tag 16`	`tag 17`	`tag 18`	`tag 19`	`tag 20`	`tag 21`	`tag 22`	`tag 23`	`tag 1+1`	`tag 1+2`	`tag 1+4`	`tag 1+8`
`e_`	`val 0`	`val 1`	`val 2`	`val 3`	`val 4`	`val 5`	`val 6`	`val 7`	`val 8`	`val 9`	`val 10`	`val 11`	`val 12`	`val 13`	`val 14`	`val 15`
`f_`	`val 16`	`val 17`	`val 18`	`val 19`	`false`	`true`	`null`	`undef`	`val 1+1`	`float 16`	`float 32`	`float 64`				`break`

Legend:

1+1 = 1 header byte + 1 data byte (24...255)
1+2 = 1 header byte + 2 data bytes (256...65535)
1+4 = 1 header byte + 4 data bytes
1+8 = 1 header byte + 8 data bytes
int = non-negative integer
neg = negative integer
bstr = byte string + length
str = UTF-8 text string + length
arr = array + length
map = map + length
tag = semantic tag + value
val = simple value
false = simple value 20
true = simple value 21
null = simple value 22
undef = simple value 23
float 16/32/64 = half/single/double precision float
indef = indefinite length
break = stop code for indefinite items

The CBOR, dCBOR, and Gordian Envelope Book

CBOR Header Bytes