ASCII

Updated: 03/05/2023 by Computer Hope

ASCII may refer to any of the following:

1. Short for American Standard Code for Information Interchange, ASCII is a standard that assigns letters, numbers, and other characters in the 256 slots available in the 8-bit code. The ASCII decimal (Dec) number is created from binary, which is the language of all computers. As shown in the table below, the lowercase "h" character (Char) has a decimal value of 104, which is "01101000" in binary.

ASCII was developed and published in 1963 by the X3 committee, a part of the ASA (American Standards Association). The ASCII standard was published as ASA X3.4-1963, with ten revisions of the standard being published between 1967 and 1986.

ASCII sections

The ASCII table is divided into three different sections.

Tip

The standard ASCII consists of 128 (27) characters. Everything beyond standard ASCII is extended (28).

  • Non-printable, system codes between 0 and 31.
  • Lower ASCII, between 32 and 127. This table originates from the older American systems, which worked on 7-bit character tables.
  • Higher ASCII (extended ASCII), between 128 and 255. This portion is programmable; characters are based on the language of your operating system or program you are using. Foreign letters are also placed in this section.

Standard or lower ASCII characters and codes

Char Dec Binary Char Dec Binary Char Dec Binary
! 033 00100001 A 065 01000001 a 097 01100001
" 034 00100010 B 066 01000010 b 098 01100010
# 035 00100011 C 067 01000011 c 099 01100011
$ 036 00100100 D 068 01000100 d 100 01100100
% 037 00100101 E 069 01000101 e 101 01100101
& 038 00100110 F 070 01000110 f 102 01100110
' 039 00100111 G 071 01000111 g 103 01100111
( 040 00101000 H 072 01001000 h 104 01101000
) 041 00101001 I 073 01001001 i 105 01101001
* 042 00101010 J 074 01001010 j 106 01101010
+ 043 00101011 K 075 01001011 k 107 01101011
, 044 00101100 L 076 01001100 l 108 01101100
- 045 00101101 M 077 01001101 m 109 01101101
. 046 00101110 N 078 01001110 n 110 01101110
/ 047 00101111 O 079 01001111 o 111 01101111
0 048 00110000 P 080 01010000 p 112 01110000
1 049 00110001 Q 081 01010001 q 113 01110001
2 050 00110010 R 082 01010010 r 114 01110010
3 051 00110011 S 083 01010011 s 115 01110011
4 052 00110100 T 084 01010100 t 116 01110100
5 053 00110101 U 085 01010101 u 117 01110101
6 054 00110110 V 086 01010110 v 118 01110110
7 055 00110111 W 087 01010111 w 119 01110111
8 056 00111000 X 088 01011000 x 120 01111000
9 057 00111001 Y 089 01011001 y 121 01111001
: 058 00111010 Z 090 01011010 z 122 01111010
; 059 00111011 [ 091 01011011 { 123 01111011
< 060 00111100 \ 092 01011100 | 124 01111100
= 061 00111101 ] 093 01011101 } 125 01111101
> 062 00111110 ^ 094 01011110 ~ 126 01111110
? 063 00111111 _ 095 01011111   127 01111111
@ 064 01000000 ` 096 01100000      

Extended ASCII characters and codes

Extended ASCII uses eight instead of seven bits, which adds 128 additional characters. This gives extended ASCII the ability for extra characters, such as special symbols, foreign language letters, and drawing characters as shown below.

Extended or Higher ASCII characters and codes

Higher ASCII chart

How do you pronounce ASCII?

ASCII is pronounced as as-key.

Do all computers use ASCII?

Although most computers do use ASCII, other formats like EBCDIC (Extended Binary Coded Decimal Interchange Code) are still used with IBM mainframes and some tape drives.

Limitations of ASCII

Only having the ability to support 256 characters is limiting for many languages and impossible for Asia languages like Chinese. To help overcome this limitation, Unicode was created and adopted by all countries.

Convert text into ASCII

Use the following tool to convert any text into their Decimal ASCII values.


2. While in an FTP (file transfer protocol) session, ascii is also a command to switch to ascii file transfer mode.

ASCII Art, ASCII printer, Character code, Codepage, Computer acronyms, EBCDIC, Programming terms, Typography terms, Unicode