ASCII Table
ASCII (American Standard Code for Information Interchange) is a standard character encoding used in telecommunication. They represent text in, telecommunications equipment, and devices. These include numbers, upper and lowercase English letters, functions, punctuation symbols, and some other symbols. In total, there are 256 ASCII characters, and can be broadly divided into three categories:
- ASCII control characters (0-31 and 127)
- ASCII printable characters (32-126) (most commonly referred)
- Extended ASCII characters (128-255)
Below are the ASCII values of printable characters (33, 126):
| Character | Character Name | ASCII code | Character | Character Name | ASCII code | Character | Character Name | ASCII code | ||
|---|---|---|---|---|---|---|---|---|---|---|
| ! | Exclamation point | 33 | A | Uppercase a | 65 | a | Lowercase a | 97 | ||
| “ | Double quotation | 34 | B | Uppercase b | 66 | b | Lowercase b | 98 | ||
| # | Number sign | 35 | C | Uppercase c | 67 | c | Lowercase c | 99 | ||
| $ | Dollar sign | 36 | D | Uppercase d | 68 | d | Lowercase d | 100 | ||
| % | Percent sign | 37 | E | Uppercase e | 69 | e | Lowercase e | 101 | ||
| & | ampersand | 38 | F | Uppercase f | 70 | f | Lowercase f | 102 | ||
| ‘ | apostrophe | 39 | G | Uppercase g | 71 | g | Lowercase g | 103 | ||
| ( | Left parenthesis | 40 | H | Uppercase h | 72 | h | Lowercase h | 104 | ||
| ) | Right parenthesis | 41 | I | Uppercase i | 73 | i | Lowercase i | 105 | ||
| * | asterisk | 42 | J | Uppercase j | 74 | j | Lowercase j | 106 | ||
| + | Plus sign | 43 | K | Uppercase k | 75 | k | Lowercase k | 107 | ||
| , | comma | 44 | L | Uppercase l | 76 | l | Lowercase l | 108 | ||
| – | hyphen | 45 | M | Uppercase m | 77 | m | Lowercase m | 109 | ||
| . | period | 46 | N | Uppercase n | 78 | n | Lowercase n | 110 | ||
| / | slash | 47 | O | Uppercase o | 79 | o | Lowercase o | 111 | ||
| 0 | zero | 48 | P | Uppercase p | 80 | p | Lowercase p | 112 | ||
| 1 | one | 49 | Q | Uppercase q | 81 | q | Lowercase q | 113 | ||
| 2 | two | 50 | R | Uppercase r | 82 | r | Lowercase r | 114 | ||
| 3 | three | 51 | S | uppercases | 83 | s | Lowercase s | 115 | ||
| 4 | four | 52 | T | Uppercase t | 84 | t | Lowercase t | 116 | ||
| 5 | five | 53 | U | Uppercase u | 85 | u | Lowercase u | 117 | ||
| 6 | six | 54 | V | Uppercase v | 86 | v | Lowercase v | 118 | ||
| 7 | seven | 55 | W | Uppercase w | 87 | w | Lowercase w | 119 | ||
| 8 | eight | 56 | X | Uppercase x | 88 | x | Lowercase x | 120 | ||
| 9 | nine | 57 | Y | Uppercase y | 89 | y | Lowercase y | 121 | ||
| : | colon | 58 | Z | Uppercase z | 90 | z | Lowercase z | 122 | ||
| ; | semi-colon | 59 | [ | Left square bracket | 91 | { | Left curly brace | 123 | ||
| < | Less-than sign | 60 | \ | backslash | 92 | | | Vertical bar | 124 | ||
| = | Equals sign | 61 | ] | Right square bracket | 93 | } | Right curly brace | 125 | ||
| > | Greater-than sign | 62 | ^ | caret | 94 | ~ | tilde | 126 | ||
| ? | Question mark | 63 | _ | underscore | 95 | |||||
| @ | At sign | 64 | ` | Grave accent | 96 |
So what’s before 33 and beyond 126?
- ASCII values before 32 (0-31) are control characters. A character code is often used in in-band signaling as a reference point in a set of characters to avoid adding additional symbols to the text.
- At 32, we have space, it is included as printed characters, however, it’s not wrong to say space could also serve as a control character.
- At 127, we have DEL (delete), which is a control character.
- After 127, (128-255), we have Extended ASCII characters representing mathematical and other symbols that are not represented as keys and are not used in general.
Below are the ASCII values of control characters (0-31, 127):
| Character | Character Name | ASCII Code | Character | Character Name | ASCII Code | Character | Character Name | ASCII Code | ||
|---|---|---|---|---|---|---|---|---|---|---|
| NULL | Null character | 00 | VT | Vertical tab | 11 | SYN | Synchronous idle | 22 | ||
| SOH | Start of header | 01 | FF | Form feed | 12 | ETB | End of trans. Block | 23 | ||
| STX | Start of text | 02 | CR | Carriage return | 13 | CAN | cancel | 24 | ||
| ETX | End of text | 03 | SO | Shift out | 14 | EM | End of medium | 25 | ||
| EOT | End of transmission | 04 | SI | Shift in | 15 | SUB | substitute | 26 | ||
| ENQ | enquiry | 05 | DLE | Data link escape | 16 | ESC | escape | 27 | ||
| ACK | acknowledge | 06 | DC1 | Device control 1 | 17 | FS | File separator | 28 | ||
| BEL | bell | 07 | DC2 | Device control 2 | 18 | GS | Group separator | 29 | ||
| BS | backspace | 08 | DC3 | Device control 3 | 19 | RS | Record separator | 30 | ||
| HT | Horizontal tab | 09 | DC4 | Device control 4 | 20 | US | Unit separator | 31 | ||
| LF | Line feed | 10 | NAK | Negative acknowledge | 21 | DEL | delete | 127 |
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