What is ASCII and why 128 characters?

ASCII is a character encoding from the 1960s that maps numbers to letters, digits, punctuation, and control codes. It uses 7 bits, which allows exactly 128 values — enough for English text and teleprinter control at a time when every bit was expensive.

What is the difference between ASCII and Unicode?

ASCII covers 128 characters, essentially English only. Unicode covers virtually every writing system in use, with over a hundred thousand characters. Unicode was designed so its first 128 code points match ASCII exactly, which is why ASCII text is valid UTF-8.

What are the control characters (0–31) for?

They were commands rather than printable symbols — controlling printers, terminals, and data transmission. A few remain essential today: 9 is tab, 10 is line feed, and 13 is carriage return. Most of the others are now historical curiosities.

How do I type a character from its code?

In HTML use the entity form, such as A for A. In most programming languages a function like chr() or String.fromCharCode() converts a number to its character. On Windows you can also hold Alt and type the decimal code on the numeric keypad.

ASCII Table

Search, copy, and link straight to any row.

Search the table

Dec	Hex	Character	HTML entity
0	0x00	NUL (null)
1	0x01	SOH
2	0x02	STX
3	0x03	ETX
4	0x04	EOT
5	0x05	ENQ
6	0x06	ACK
7	0x07	BEL (bell)
8	0x08	BS (backspace)
9	0x09	TAB
10	0x0A	LF (line feed)
11	0x0B	VT
12	0x0C	FF
13	0x0D	CR (carriage return)
14	0x0E	SO
15	0x0F	SI
16	0x10	DLE
17	0x11	DC1
18	0x12	DC2
19	0x13	DC3
20	0x14	DC4
21	0x15	NAK
22	0x16	SYN
23	0x17	ETB
24	0x18	CAN
25	0x19	EM
26	0x1A	SUB
27	0x1B	ESC (escape)
28	0x1C	FS
29	0x1D	GS
30	0x1E	RS
31	0x1F	US
32	0x20	Space
33	0x21	!	!
34	0x22	"	"
35	0x23	#	#
36	0x24	$	$
37	0x25	%	%
38	0x26	&	&
39	0x27	'	'
40	0x28	(	(
41	0x29	)	)
42	0x2A	*	*
43	0x2B	+	+
44	0x2C	,	,
45	0x2D	-	-
46	0x2E	.	.
47	0x2F	/	/
48	0x30	0	0
49	0x31	1	1
50	0x32	2	2
51	0x33	3	3
52	0x34	4	4
53	0x35	5	5
54	0x36	6	6
55	0x37	7	7
56	0x38	8	8
57	0x39	9	9
58	0x3A	:	:
59	0x3B	;	;
60	0x3C	<	<
61	0x3D	=	=
62	0x3E	>	>
63	0x3F	?	?
64	0x40	@	@
65	0x41	A	A
66	0x42	B	B
67	0x43	C	C
68	0x44	D	D
69	0x45	E	E
70	0x46	F	F
71	0x47	G	G
72	0x48	H	H
73	0x49	I	I
74	0x4A	J	J
75	0x4B	K	K
76	0x4C	L	L
77	0x4D	M	M
78	0x4E	N	N
79	0x4F	O	O
80	0x50	P	P
81	0x51	Q	Q
82	0x52	R	R
83	0x53	S	S
84	0x54	T	T
85	0x55	U	U
86	0x56	V	V
87	0x57	W	W
88	0x58	X	X
89	0x59	Y	Y
90	0x5A	Z	Z
91	0x5B	[	[
92	0x5C	\	\
93	0x5D	]	]
94	0x5E	^	^
95	0x5F	_	_
96	0x60	`	`
97	0x61	a	a
98	0x62	b	b
99	0x63	c	c
100	0x64	d	d
101	0x65	e	e
102	0x66	f	f
103	0x67	g	g
104	0x68	h	h
105	0x69	i	i
106	0x6A	j	j
107	0x6B	k	k
108	0x6C	l	l
109	0x6D	m	m
110	0x6E	n	n
111	0x6F	o	o
112	0x70	p	p
113	0x71	q	q
114	0x72	r	r
115	0x73	s	s
116	0x74	t	t
117	0x75	u	u
118	0x76	v	v
119	0x77	w	w
120	0x78	x	x
121	0x79	y	y
122	0x7A	z	z
123	0x7B	{	{
124	0x7C	\|	\|
125	0x7D	}	}
126	0x7E	~	~
127	0x7F	DEL (delete)

The ASCII table lists all 128 characters in the original ASCII standard, with their decimal and hexadecimal codes and HTML entities. Codes 0 to 31 are control characters used for formatting and device control, 32 is the space, and 33 to 126 are the printable letters, digits, and punctuation. Search the table, copy any row, or link straight to a specific code. It runs entirely in your browser.

How to use it

Type in the search box to filter by decimal, hex, character, or name.
Use the copy button on any row to grab the code and character.
Link directly to a character with its code, for example #row-65.

Examples

65 = 0x41 = A, the first uppercase letter.
10 = 0x0A = LF, the line feed that ends lines on Unix systems.

Frequently asked questions

What is ASCII and why 128 characters?: ASCII is a character encoding from the 1960s that maps numbers to letters, digits, punctuation, and control codes. It uses 7 bits, which allows exactly 128 values — enough for English text and teleprinter control at a time when every bit was expensive.
What is the difference between ASCII and Unicode?: ASCII covers 128 characters, essentially English only. Unicode covers virtually every writing system in use, with over a hundred thousand characters. Unicode was designed so its first 128 code points match ASCII exactly, which is why ASCII text is valid UTF-8.
What are the control characters (0–31) for?: They were commands rather than printable symbols — controlling printers, terminals, and data transmission. A few remain essential today: 9 is tab, 10 is line feed, and 13 is carriage return. Most of the others are now historical curiosities.
How do I type a character from its code?: In HTML use the entity form, such as A for A. In most programming languages a function like chr() or String.fromCharCode() converts a number to its character. On Windows you can also hold Alt and type the decimal code on the numeric keypad.

ASCII Table

How to use it

Examples

Frequently asked questions

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