ASCII Table

ASCII (American Standard Code for Information Interchange) is a 7-bit character encoding that maps the numbers 0–127 to characters. Established in 1963, it covers the digits, the uppercase and lowercase Latin letters, common punctuation, and 33 non-printing control codes — and it remains the foundation of modern text, because UTF-8 reuses these same 128 code points unchanged. The table below lists every code in decimal, hexadecimal, octal, and binary alongside its character. Codes 0–31 and 127 are control characters (such as TAB, line feed, and carriage return); 32–126 are the printable characters you can type and see.

Full table

Dec	Hex	Oct	Bin	Char
0	0x0	000	0000000	NUL
1	0x1	001	0000001	SOH
2	0x2	002	0000010	STX
3	0x3	003	0000011	ETX
4	0x4	004	0000100	EOT
5	0x5	005	0000101	ENQ
6	0x6	006	0000110	ACK
7	0x7	007	0000111	BEL
8	0x8	010	0001000	BS
9	0x9	011	0001001	HT
10	0xA	012	0001010	LF
11	0xB	013	0001011	VT
12	0xC	014	0001100	FF
13	0xD	015	0001101	CR
14	0xE	016	0001110	SO
15	0xF	017	0001111	SI
16	0x10	020	0010000	DLE
17	0x11	021	0010001	DC1
18	0x12	022	0010010	DC2
19	0x13	023	0010011	DC3
20	0x14	024	0010100	DC4
21	0x15	025	0010101	NAK
22	0x16	026	0010110	SYN
23	0x17	027	0010111	ETB
24	0x18	030	0011000	CAN
25	0x19	031	0011001	EM
26	0x1A	032	0011010	SUB
27	0x1B	033	0011011	ESC
28	0x1C	034	0011100	FS
29	0x1D	035	0011101	GS
30	0x1E	036	0011110	RS
31	0x1F	037	0011111	US
32	0x20	040	0100000	SP (space)
33	0x21	041	0100001	!
34	0x22	042	0100010	"
35	0x23	043	0100011	#
36	0x24	044	0100100	$
37	0x25	045	0100101	%
38	0x26	046	0100110	&
39	0x27	047	0100111	'
40	0x28	050	0101000	(
41	0x29	051	0101001	)
42	0x2A	052	0101010	*
43	0x2B	053	0101011	+
44	0x2C	054	0101100	,
45	0x2D	055	0101101	-
46	0x2E	056	0101110	.
47	0x2F	057	0101111	/
48	0x30	060	0110000	0
49	0x31	061	0110001	1
50	0x32	062	0110010	2
51	0x33	063	0110011	3
52	0x34	064	0110100	4
53	0x35	065	0110101	5
54	0x36	066	0110110	6
55	0x37	067	0110111	7
56	0x38	070	0111000	8
57	0x39	071	0111001	9
58	0x3A	072	0111010	:
59	0x3B	073	0111011	;
60	0x3C	074	0111100	<
61	0x3D	075	0111101	=
62	0x3E	076	0111110	>
63	0x3F	077	0111111	?
64	0x40	100	1000000	@
65	0x41	101	1000001	A
66	0x42	102	1000010	B
67	0x43	103	1000011	C
68	0x44	104	1000100	D
69	0x45	105	1000101	E
70	0x46	106	1000110	F
71	0x47	107	1000111	G
72	0x48	110	1001000	H
73	0x49	111	1001001	I
74	0x4A	112	1001010	J
75	0x4B	113	1001011	K
76	0x4C	114	1001100	L
77	0x4D	115	1001101	M
78	0x4E	116	1001110	N
79	0x4F	117	1001111	O
80	0x50	120	1010000	P
81	0x51	121	1010001	Q
82	0x52	122	1010010	R
83	0x53	123	1010011	S
84	0x54	124	1010100	T
85	0x55	125	1010101	U
86	0x56	126	1010110	V
87	0x57	127	1010111	W
88	0x58	130	1011000	X
89	0x59	131	1011001	Y
90	0x5A	132	1011010	Z
91	0x5B	133	1011011	[
92	0x5C	134	1011100	\
93	0x5D	135	1011101	]
94	0x5E	136	1011110	^
95	0x5F	137	1011111	_
96	0x60	140	1100000	`
97	0x61	141	1100001	a
98	0x62	142	1100010	b
99	0x63	143	1100011	c
100	0x64	144	1100100	d
101	0x65	145	1100101	e
102	0x66	146	1100110	f
103	0x67	147	1100111	g
104	0x68	150	1101000	h
105	0x69	151	1101001	i
106	0x6A	152	1101010	j
107	0x6B	153	1101011	k
108	0x6C	154	1101100	l
109	0x6D	155	1101101	m
110	0x6E	156	1101110	n
111	0x6F	157	1101111	o
112	0x70	160	1110000	p
113	0x71	161	1110001	q
114	0x72	162	1110010	r
115	0x73	163	1110011	s
116	0x74	164	1110100	t
117	0x75	165	1110101	u
118	0x76	166	1110110	v
119	0x77	167	1110111	w
120	0x78	170	1111000	x
121	0x79	171	1111001	y
122	0x7A	172	1111010	z
123	0x7B	173	1111011	{
124	0x7C	174	1111100	\|
125	0x7D	175	1111101	}
126	0x7E	176	1111110	~
127	0x7F	177	1111111	DEL

Notes

Control codes 0–31 originally controlled teletypes; many are still used (CR=13, LF=10, TAB=9, NUL=0).
Codes 128–255 depend on codepage — use UTF-8 for anything beyond ASCII.

Frequently asked questions

What is ASCII?

American Standard Code for Information Interchange — a 7-bit character encoding established in 1963 that maps numbers 0–127 to characters: digits, uppercase and lowercase Latin letters, common punctuation, and 33 control codes. It's the foundation of nearly every modern text encoding (UTF-8 includes ASCII as its first 128 code points unchanged), and underlies virtually every text protocol on the internet.

What are control codes?

Codes 0–31 and 127 are non-printing characters originally designed to control teletype machines and terminals. The most commonly seen today: NUL (0) string terminator in C; BEL (7) the terminal beep; BS (8) backspace; HT (9) tab; LF (10) line feed (Unix newline); CR (13) carriage return (paired with LF for Windows newlines); ESC (27) escape, the start of ANSI terminal codes; DEL (127) delete.

What's the difference between ASCII and Unicode?

ASCII is 128 characters in 7 bits. Unicode is over 149,000 characters across nearly 1.2 million possible code points. UTF-8 is the dominant encoding of Unicode and is backward-compatible with ASCII — the first 128 code points of UTF-8 are byte-for-byte identical to ASCII. So all ASCII text is valid UTF-8; the reverse isn't necessarily true.

Why do some characters take more bytes in UTF-8?

ASCII characters take 1 byte each. Most Latin-extended characters (é, ñ, ö) take 2. CJK characters (中, あ, 한) take 3. Emoji and rare symbols take 4. UTF-8 is a variable-length encoding — the first byte tells you how long the character is. This is why a string of 100 emoji takes 400 bytes.

What about codes 128–255?

Not part of ASCII proper. Various 8-bit extensions assign meaning differently: ISO-8859-1 (Latin-1) covers Western European characters; Windows-1252 is similar but adds smart quotes and em-dashes; KOI8-R covers Cyrillic. These 'extended ASCII' codepages are mostly obsolete — modern systems use Unicode and UTF-8 for everything beyond ASCII.

Why does Windows use CR+LF and Unix use LF?

Historical accident. Teletypes physically required two operations to start a new line: carriage return (move print head to left) and line feed (advance paper). Mac OS classic used CR alone; DEC and Unix used LF alone; Windows kept the original CR+LF. Modern git, editors, and terminals usually handle this transparently, but the difference still causes occasional cross-platform headaches.

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