ASCII table

ASCII assigns a number to 128 characters — the digits, the unaccented Latin letters, common punctuation, and 33 control codes that were never meant to be printed. Every one of them is listed below in decimal, hexadecimal, octal and binary, with its HTML entity number.

The first 32 codes and the last one are controls. Most are historical, from an era of teleprinters and paper tape, but a handful still run everything you type: 9 is Tab, 10 is the Unix newline, 13 is the carriage return that Windows pairs with it, and 27 starts every ANSI escape sequence your terminal uses for colour.

ASCII is the first 128 code points of Unicode, unchanged, which is why it is still the common denominator of nearly every encoding in use. UTF-8 was designed so that any pure-ASCII file is already valid UTF-8, byte for byte.

Control codes

0–31, 127

Dec	Hex	Oct	Binary	Char	Name
0	00	000	00000000	NUL	NullString terminator in C. Not a printable character.
1	01	001	00000001	SOH	Start of headingHistorical; framed the header of a transmission block.
2	02	002	00000010	STX	Start of textHistorical; marked where the message body began.
3	03	003	00000011	ETX	End of textSent by Ctrl+C, which is why that key interrupts a program.
4	04	004	00000100	EOT	End of transmissionSent by Ctrl+D; closes stdin in a Unix shell.
5	05	005	00000101	ENQ	EnquiryHistorical; asked the far end to identify itself.
6	06	006	00000110	ACK	AcknowledgePositive response in older serial protocols.
7	07	007	00000111	BEL	BellRings the terminal bell. Written \a in C.
8	08	010	00001000	BS	BackspaceMoves the cursor back one column. Written \b.
9	09	011	00001001	HT	Horizontal tabThe Tab key. Written \t.
10	0A	012	00001010	LF	Line feedThe Unix newline. Written \n.
11	0B	013	00001011	VT	Vertical tabRare; advances to the next vertical tab stop. Written \v.
12	0C	014	00001100	FF	Form feedPage break for printers. Written \f.
13	0D	015	00001101	CR	Carriage returnReturns to column one. Paired with LF on Windows. Written \r.
14	0E	016	00001110	SO	Shift outHistorical; switched to an alternate character set.
15	0F	017	00001111	SI	Shift inHistorical; switched back to the standard set.
16	10	020	00010000	DLE	Data link escapeHistorical; made the next bytes control data.
17	11	021	00010001	DC1	Device control 1XON — resumes a paused transmission. Sent by Ctrl+Q.
18	12	022	00010010	DC2	Device control 2Historical device control.
19	13	023	00010011	DC3	Device control 3XOFF — pauses transmission. Sent by Ctrl+S.
20	14	024	00010100	DC4	Device control 4Historical device control.
21	15	025	00010101	NAK	Negative acknowledgeNegative response in older serial protocols.
22	16	026	00010110	SYN	Synchronous idleFilled silence on synchronous links.
23	17	027	00010111	ETB	End of transmission blockHistorical; ended one block of a longer message.
24	18	030	00011000	CAN	CancelDiscards the data sent before it.
25	19	031	00011001	EM	End of mediumMarked the physical end of a tape or card deck.
26	1A	032	00011010	SUB	SubstituteEnd-of-file marker in DOS and CP/M. Sent by Ctrl+Z.
27	1B	033	00011011	ESC	EscapeStarts an ANSI escape sequence — terminal colours and cursor moves.
28	1C	034	00011100	FS	File separatorCoarsest of the four data separators.
29	1D	035	00011101	GS	Group separatorSeparates groups within a file.
30	1E	036	00011110	RS	Record separatorSeparates records within a group.
31	1F	037	00011111	US	Unit separatorFinest separator; occasionally used as a field delimiter.
127	7F	177	01111111	DEL	DeleteAll bits punched on paper tape, which is why it is at the top.

Space

Dec	Hex	Oct	Binary	Char	HTML	Name
32	20	040	00100000			Space

Punctuation and symbols

33–47, 58–64, 91–96, 123–126

Dec	Hex	Oct	Binary	Char	HTML	Name
33	21	041	00100001	!	!	Exclamation mark
34	22	042	00100010	"	"	Quotation mark
35	23	043	00100011	#	#	Number sign
36	24	044	00100100	$	$	Dollar sign
37	25	045	00100101	%	%	Percent sign
38	26	046	00100110	&	&	Ampersand
39	27	047	00100111	'	'	Apostrophe
40	28	050	00101000	(	(	Left parenthesis
41	29	051	00101001	)	)	Right parenthesis
42	2A	052	00101010	*	*	Asterisk
43	2B	053	00101011	+	+	Plus sign
44	2C	054	00101100	,	,	Comma
45	2D	055	00101101	-	-	Hyphen-minus
46	2E	056	00101110	.	.	Full stop
47	2F	057	00101111	/	/	Solidus
58	3A	072	00111010	:	:	Colon
59	3B	073	00111011	;	;	Semicolon
60	3C	074	00111100	<	<	Less-than sign
61	3D	075	00111101	=	=	Equals sign
62	3E	076	00111110	>	>	Greater-than sign
63	3F	077	00111111	?	?	Question mark
64	40	100	01000000	@	@	Commercial at
91	5B	133	01011011	[	[	Left square bracket
92	5C	134	01011100	\	\	Reverse solidus
93	5D	135	01011101	]	]	Right square bracket
94	5E	136	01011110	^	^	Circumflex accent
95	5F	137	01011111	_	_	Low line
96	60	140	01100000	`	`	Grave accent
123	7B	173	01111011	{	{	Left curly bracket
124	7C	174	01111100	\|	\|	Vertical line
125	7D	175	01111101	}	}	Right curly bracket
126	7E	176	01111110	~	~	Tilde

Digits

48–57

Dec	Hex	Oct	Binary	Char	HTML	Name
48	30	060	00110000	0	0	Digit 0
49	31	061	00110001	1	1	Digit 1
50	32	062	00110010	2	2	Digit 2
51	33	063	00110011	3	3	Digit 3
52	34	064	00110100	4	4	Digit 4
53	35	065	00110101	5	5	Digit 5
54	36	066	00110110	6	6	Digit 6
55	37	067	00110111	7	7	Digit 7
56	38	070	00111000	8	8	Digit 8
57	39	071	00111001	9	9	Digit 9

Letters

65–90, 97–122

Dec	Hex	Oct	Binary	Char	HTML	Name
65	41	101	01000001	A	A	Capital letter A
66	42	102	01000010	B	B	Capital letter B
67	43	103	01000011	C	C	Capital letter C
68	44	104	01000100	D	D	Capital letter D
69	45	105	01000101	E	E	Capital letter E
70	46	106	01000110	F	F	Capital letter F
71	47	107	01000111	G	G	Capital letter G
72	48	110	01001000	H	H	Capital letter H
73	49	111	01001001	I	I	Capital letter I
74	4A	112	01001010	J	J	Capital letter J
75	4B	113	01001011	K	K	Capital letter K
76	4C	114	01001100	L	L	Capital letter L
77	4D	115	01001101	M	M	Capital letter M
78	4E	116	01001110	N	N	Capital letter N
79	4F	117	01001111	O	O	Capital letter O
80	50	120	01010000	P	P	Capital letter P
81	51	121	01010001	Q	Q	Capital letter Q
82	52	122	01010010	R	R	Capital letter R
83	53	123	01010011	S	S	Capital letter S
84	54	124	01010100	T	T	Capital letter T
85	55	125	01010101	U	U	Capital letter U
86	56	126	01010110	V	V	Capital letter V
87	57	127	01010111	W	W	Capital letter W
88	58	130	01011000	X	X	Capital letter X
89	59	131	01011001	Y	Y	Capital letter Y
90	5A	132	01011010	Z	Z	Capital letter Z
97	61	141	01100001	a	a	Small letter a
98	62	142	01100010	b	b	Small letter b
99	63	143	01100011	c	c	Small letter c
100	64	144	01100100	d	d	Small letter d
101	65	145	01100101	e	e	Small letter e
102	66	146	01100110	f	f	Small letter f
103	67	147	01100111	g	g	Small letter g
104	68	150	01101000	h	h	Small letter h
105	69	151	01101001	i	i	Small letter i
106	6A	152	01101010	j	j	Small letter j
107	6B	153	01101011	k	k	Small letter k
108	6C	154	01101100	l	l	Small letter l
109	6D	155	01101101	m	m	Small letter m
110	6E	156	01101110	n	n	Small letter n
111	6F	157	01101111	o	o	Small letter o
112	70	160	01110000	p	p	Small letter p
113	71	161	01110001	q	q	Small letter q
114	72	162	01110010	r	r	Small letter r
115	73	163	01110011	s	s	Small letter s
116	74	164	01110100	t	t	Small letter t
117	75	165	01110101	u	u	Small letter u
118	76	166	01110110	v	v	Small letter v
119	77	167	01110111	w	w	Small letter w
120	78	170	01111000	x	x	Small letter x
121	79	171	01111001	y	y	Small letter y
122	7A	172	01111010	z	z	Small letter z

FAQ

What is the difference between ASCII and UTF-8?

ASCII defines 128 characters, numbered 0 to 127. UTF-8 is an encoding for the whole of Unicode — over 150,000 characters — and it encodes those first 128 as single bytes with exactly the ASCII values. So every ASCII file is a valid UTF-8 file, but the reverse only holds if the text stays inside those 128 characters.

Why does the table stop at 127?

ASCII is a 7-bit standard, and 2⁷ is 128. Codes 128–255 are not ASCII: they belong to whichever 8-bit extension is in play — Windows-1252, ISO-8859-1, and others — which is precisely why they disagree with each other and why text with accents arrives mangled so often.

What is the ASCII code for space?

Decimal 32, hex 20. It is a printable character despite looking like nothing, which is why it sits outside the control range that ends at 31.

Why is DEL at 127 instead of 0?

Paper tape. Deleting a character meant punching out every hole in its position, and all seven bits punched is 127. A deleted character could not be un-deleted, which is also where the modern meaning comes from.

What is the difference between CR and LF?

CR (13) returns the print head to column one; LF (10) advances one line. Unix and macOS end lines with LF alone, Windows uses CR followed by LF, and that disagreement is the reason a file can show up as one long line or with stray ^M characters.