yihleego / base62

Base62 implementation for Go

Base62

The base62 encoding scheme uses 62 characters. The characters consist of the capital letters A-Z, the lower case letters a-z and the numbers 0–9. It is a binary-to-text encoding schemes that represent binary data in an ASCII string format.

Base62 Alphabet

0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz

Base62 table

Decimal	Binary	Base62		Decimal	Binary	Base62		Decimal	Binary	Base62		Decimal	Binary	Base62
0	000000	0		16	010000	G		32	100000	W		48	110000	m
1	000001	1		17	010001	H		33	100001	X		49	110001	n
2	000010	2		18	010010	I		34	100010	Y		50	110010	o
3	000011	3		19	010011	J		35	100011	Z		51	110011	p
4	000100	4		20	010100	K		36	100100	a		52	110100	q
5	000101	5		21	010101	L		37	100101	b		53	110101	r
6	000110	6		22	010110	M		38	100110	c		54	110110	s
7	000111	7		23	010111	N		39	100111	d		55	110111	t
8	001000	8		24	011000	O		40	101000	e		56	111000	u
9	001001	9		25	011001	P		41	101001	f		57	111001	v
10	001010	A		26	011010	Q		42	101010	g		58	111010	w
11	001011	B		27	011011	R		43	101011	h		59	111011	x
12	001100	C		28	011100	S		44	101100	i		60	111100	y
13	001101	D		29	011101	T		45	101101	j		61	111101	z
14	001110	E		30	011110	U		46	101110	k
15	001111	F		31	011111	V		47	101111	l

See: Wikipedia Base62

Usage

Encode

src := []byte("Hello, World!")
encoded := base62.StdEncoding.Encode(src)
// {49, 119, 74, 102, 114, 122, 118, 100, 98, 116, 88, 85, 79, 108, 85, 106, 85, 102}

EncodeToString

src := []byte("Hello, World!")
encoded := base62.StdEncoding.EncodeToString(src)
// 1wJfrzvdbtXUOlUjUf

Decode

src := []byte{49, 119, 74, 102, 114, 122, 118, 100, 98, 116, 88, 85, 79, 108, 85, 106, 85, 102}
decoded, err := base62.StdEncoding.Decode(src)
// {72, 101, 108, 108, 111, 44, 32, 87, 111, 114, 108, 100, 33}
str := string(decoded)
// Hello, World!

DecodeString

src := "1wJfrzvdbtXUOlUjUf"
decoded, err := base62.StdEncoding.DecodeString(src)
// {72, 101, 108, 108, 111, 44, 32, 87, 111, 114, 108, 100, 33}
str := string(decoded)
// Hello, World!

Custom alphabet

// 62-byte string
encoding := base62.NewEncoding("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")

src := []byte("Hello, World!")
encoded := encoding.Encode(src)
// {66, 54, 84, 112, 49, 57, 53, 110, 108, 51, 104, 101, 89, 118, 101, 116, 101, 112}