ASCII Characters

By Xah Lee. Date: 2010-09-03. Last updated: 2024-12-01.

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What Are ASCII Characters

ASCII characters is a character set of 128 characters, each with a name and an integer ID (aka Unicode Codepoint).

The character set includes printable characters and control characters.
Printable Characters includes digits 0 to 9, letters A to Z uppercase and lowercase, punctuations. There are 95 printable characters.
Control Characters are used to represent tab, start text, null, escape, bell (audio alert), end of line, end of file, end of transmission, abort, etc. Control Characters have ID 0 to 31, and 127. There are 33 control characters.
ASCII character set is identical to Unicode characters with ID from from 0 to 127 inclusive, and each char also have the same ID.
ASCII is abbreviation for American Standard Code for Information Interchange, created in 1960s.
The ASCII characters can be represented by 7 binary digits. So its sometimes called 7 bits ASCII.

Here's the printable ASCII characters, in the order of their ID (aka codepoint):

!"#$%&'()*+,-./
0123456789
:;<=>?@
ABCDEFGHIJKLMNOPQRSTUVWXYZ
[\]^_`
abcdefghijklmnopqrstuvwxyz
{|}~

Control Characters have various notations.

By their integer ID (codepoint) in decimal. (e.g. Carriage return is 13.)
By codepoint in hexadecimal. (e.g. Carriage return is 0D.)
By standardized abbrev. (e.g. Carriage return is CR.)
By Unicode glyph. (e.g. Carriage return is ␍.) 〔see Unicode: Symbols for ASCII Control Characters ␀〕
By caret notation. (e.g. Carriage return is ^M.) (Caret notation is heavily used in emacs. 〔see Emacs: Newline Convention〕)
In programing languages, some have C escape syntax in string. (e.g. Carriage return is \r.)

Here's the complete ASCII table.

ASCII Control Characters
ID	Hex	Abbr	Unicode Symbol	Caret Notation	C Escape Syntax	Description
0	00	NUL	␀	^@	\0	Null character
1	01	SOH	␁	^A		Start of Header
2	02	STX	␂	^B		Start of Text
3	03	ETX	␃	^C		End of Text
4	04	EOT	␄	^D		End of Transmission
5	05	ENQ	␅	^E		Enquiry
6	06	ACK	␆	^F		Acknowledgment
7	07	BEL	␇ ⍾	^G	\a	Bell
8	08	BS	␈	^H	\b	Backspace
9	09	HT	␉	^I	\t	Horizontal Tab
10	0A	LF	␊	^J	\n	Line feed
11	0B	VT	␋	^K	\v	Vertical Tab
12	0C	FF	␌	^L	\f	Form feed
13	0D	CR	␍	^M	\r	Carriage return
14	0E	SO	␎	^N		Shift Out
15	0F	SI	␏	^O		Shift In
16	10	DLE	␐	^P		Data Link Escape
17	11	DC1	␑	^Q		Device Control 1 (oft. XON)
18	12	DC2	␒	^R		Device Control 2
19	13	DC3	␓	^S		Device Control 3 (oft. XOFF)
20	14	DC4	␔	^T		Device Control 4
21	15	NAK	␕	^U		Negative Acknowledgment
22	16	SYN	␖	^V		Synchronous Idle
23	17	ETB	␗	^W		End of Trans. Block
24	18	CAN	␘	^X		Cancel
25	19	EM	␙	^Y		End of Medium
26	1A	SUB	␚	^Z		Substitute
27	1B	ESC	␛	^[	\e	Escape
28	1C	FS	␜	^\		File Separator
29	1D	GS	␝	^]		Group Separator
30	1E	RS	␞	^^		Record Separator
31	1F	US	␟	^_		Unit Separator
ID	Hex	Abbr	Unicode Symbol	Caret Notation	C Escape Syntax	Description
127	7F	DEL	␡	^?		Delete