Jun 23, 2019

ASCII Encoding

ASCII is a 7 bit encoding standard used to represent latin characters, digits and a few special characters as bytes. It is one of the earliest character encoding standards. The ASCII standard was initially published in 1963 and comprised of 128 characters represented by bytes ranging from 0 to 127.

ASCII Control Characters

The first 32 ASCII codes are reserved for devices such as printers. These characters cannot be displayed on screen. Although, there are whitespace characters such as space, tab and newline in this list which have meaning on display devices too. The ASCII character DEL which has a code of 127 also makes this list. Given below is a table showing the ASCII control characters and their corresponding byte values.

ByteControl CharacterDescription
00NULL(Null character)
01SOH(Start of Header)
02STX(Start of Text)
03ETX(End of Text)
04EOT(End of Trans.)
05ENQ(Enquiry)
06ACK(Acknowledgement)
07BEL(Bell)
08BS(Backspace)
09HT(Horizontal Tab)
10LF(Line feed)
11VT(Vertical Tab)
12FF(Form feed)
13CR(Carriage return)
14SO(Shift Out)
15SI(Shift In)
16DLE(Data link escape)
17DC1(Device control 1)
18DC2(Device control 2)
19DC3(Device control 3)
20DC4(Device control 4)
21NAK(Negative acknowl.)
22SYN(Synchronous idle)
23ETB(End of trans. block)
24CAN(Cancel)
25EM(End of medium)
26SUB(Substitute)
27ESC(Escape)
28FS(File separator)
29GS(Group separator)
30RS(Record separator)
31US(Unit separator)
127DEL(Delete)

Printable ASCII Characters

These characters are what give ASCII their meaning. It comprises of roman letters in upper and lower case, digits and special characters that you find in most keyboards.

ByteCharacter
32space
33!
34"
35#
36$
37%
38&
39'
40(
41)
42*
43+
44,
45-
46.
47/
480
491
502
513
524
535
546
557
568
579
58:
59;
60<
61=
62>
63?
ByteCharacter
64@
65A
66B
67C
68D
69E
70F
71G
72H
73I
74J
75K
76L
77M
78N
79O
80P
81Q
82R
83S
84T
85U
86V
87W
88X
89Y
90Z
91[
92\
93]
94^
95_
ByteCharacter
96`
97a
98b
99c
100d
101e
102f
103g
104h
105i
106j
107k
108l
109m
110n
111o
112p
113q
114r
115s
116t
117u
118v
119w
120x
121y
122z
123{
124|
125}
126~

Extended ASCII Characters

With the increase in prevalence of 8, 16 and 32 bit computers, applications started storing characters using 8 bits as opposed to 7. This led to the ASCII character set being extended to support additional characters. While, there are many such standards, the ANSI standard is the most widely used. Given below are the extended ASCII characters which are represented by bytes from 128 to 255.

ByteCharacter
128Ç
129ü
130é
131â
132ä
133à
134å
135ç
136ê
137ë
138è
139ï
140î
141ì
142Ä
143Å
144É
145æ
146Æ
147ô
148ö
149ò
150û
151ù
152ÿ
153Ö
154Ü
155ø
156£
157Ø
158×
159ƒ
ByteCharacter
160á
161í
162ó
163ú
164ñ
165Ñ
166ª
167º
168¿
169®
170¬
171½
172¼
173¡
174«
175»
176
177
178
179
180
181Á
182Â
183À
184©
185
186
187
188
189¢
190¥
191
ByteCharacter
192
193
194
195
196
197
198ã
199Ã
200
201
202
203
204
205
206
207¤
208ð
209Ð
210Ê
211Ë
212È
213ı
214Í
215Î
216Ï
217
218
219
220
221¦
222Ì
223
ByteCharacter
224Ó
225ß
226Ô
227Ò
228õ
229Õ
230µ
231þ
232Þ
233Ú
234Û
235Ù
236ý
237Ý
238¯
239´
240
241±
242
243¾
244
245§
246÷
247¸
248°
249¨
250·
251¹
252³
253²
254
255nbsp