> For the complete documentation index, see [llms.txt](https://www.ctfrecipes.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.ctfrecipes.com/cryptography/general-knowledge/encoding/character-encoding/ascii.md). # ASCII **ASCII** (**A**merican **S**tandard **C**ode for **I**nformation **I**nterchange) is an early character encoding standard that represents each character as a unique number between 0 and 127. ASCII only **defines a limited set of characters**, including the English alphabet (**upper** and **lower** case), **numbers**, and a set of **common punctuation** and **control characters**. ## How it works ? ASCII encoding assigns each character a unique 7-bit binary number. This allows each character to be represented as a single byte (8 bits) in memory. Here is the entire ASCII table | Decimal | Hexadecimal | Symbol | | ------- | ----------- | ------------------------- | | 0 | 00 | NUL (Null) | | 1 | 01 | SOH (Start Of Header) | | 2 | 02 | STX (Start Of Text) | | 3 | 03 | ETX (End of Text) | | 4 | 04 | EOT (End of Transmission) | | 5 | 05 | ENQ (Enquiry) | | 6 | 06 | ACK (Acknowledge) | | 7 | 07 | BEL (Bell) | | 8 | 08 | BS (Backspace) | | 9 | 09 | HT (Horizontal tab) | | 10 | 0A | LF (New Line) | | 11 | 0B | VT (Vertical Tab) | | 12 | 0C | FF (New Page) | | 13 | 0D | CR (Carriage Return) | | 14 | 0E | SO (Shift Out) | | 15 | 0F | SI (Shift In) | | 16 | 10 | DLE (Data Link Escape) | | 17 | 11 | DC1 (Device control 1) | | 18 | 12 | DC2 (Device control 2) | | 19 | 13 | DC3 (Device control 3) | | 20 | 14 | DC4 (Device control 4) | | 21 | 15 | NAK (Negative Aknowledge) | | 22 | 16 | SYN (Synchronous idle) | | 23 | 17 | ETB (End of trans. block) | | 24 | 18 | CAN (Cancel) | | 25 | 19 | EM (End of Medium) | | 26 | 1A | SUB (Substitute) | | 27 | 1B | ESC (Escape) | | 28 | 1C | FS (File separator) | | 29 | 1D | GS (Group Separator) | | 30 | 1E | RS (Record Separator) | | 31 | 1F | US (Unit Separator) | | 32 | 20 | space | | 33 | 21 | ! | | 34 | 22 | " | | 35 | 23 | # | | 36 | 24 | $ | | 37 | 25 | % | | 38 | 26 | & | | 39 | 27 | ' | | 40 | 28 | ( | | 41 | 29 | ) | | 42 | 2A | \* | | 43 | 2B | + | | 44 | 2C | , | | 45 | 2D | - | | 46 | 2E | . | | 47 | 2F | / | | 48 | 30 | 0 | | 49 | 31 | 1 | | 50 | 32 | 2 | | 51 | 33 | 3 | | 52 | 34 | 4 | | 53 | 35 | 5 | | 54 | 36 | 6 | | 55 | 37 | 7 | | 56 | 38 | 8 | | 57 | 39 | 9 | | 58 | 3A | : | | 59 | 3B | ; | | 60 | 3C | < | | 61 | 3D | = | | 62 | 3E | > | | 63 | 3F | ? | | 64 | 40 | @ | | 65 | 41 | A | | 66 | 42 | B | | 67 | 43 | C | | 68 | 44 | D | | 69 | 45 | E | | 70 | 46 | F | | 71 | 47 | G | | 72 | 48 | H | | 73 | 49 | I | | 74 | 4A | J | | 75 | 4B | K | | 76 | 4C | L | | 77 | 4D | M | | 78 | 4E | N | | 79 | 4F | O | | 80 | 50 | P | | 81 | 51 | Q | | 82 | 52 | R | | 83 | 53 | S | | 84 | 54 | T | | 85 | 55 | U | | 86 | 56 | V | | 87 | 57 | W | | 88 | 58 | X | | 89 | 59 | Y | | 90 | 5A | Z | | 91 | 5B | \[ | | 92 | 5C | \\ | | 93 | 5D | ] | | 94 | 5E | ^ | | 95 | 5F | \_ | | 96 | 60 | \` | | 97 | 61 | a | | 98 | 62 | b | | 99 | 63 | c | | 100 | 64 | d | | 101 | 65 | e | | 102 | 66 | f | | 103 | 67 | g | | 104 | 68 | h | | 105 | 69 | i | | 106 | 6A | j | | 107 | 6B | k | | 108 | 6C | l | | 109 | 6D | m | | 110 | 6E | n | | 111 | 6F | o | | 112 | 70 | p | | 113 | 71 | q | | 114 | 72 | r | | 115 | 73 | s | | 116 | 74 | t | | 117 | 75 | u | | 118 | 76 | v | | 119 | 77 | w | | 120 | 78 | x | | 121 | 79 | y | | 122 | 7A | z | | 123 | 7B | { | | 124 | 7C | \| | | 125 | 7D | ] | | 126 | 7E | \~ | | 127 | 7F | DEL | There is an extended ASCII table that includes symbols till 255 : | Decimal | Hexadecimal | Symbol | | ------- | ----------- | ------ | | 128 | 80 | € | | 129 | 81 |  | | 130 | 82 | ‚ | | 131 | 83 | ƒ | | 132 | 84 | „ | | 133 | 85 | … | | 134 | 86 | † | | 135 | 87 | ‡ | | 136 | 88 | ˆ | | 137 | 89 | ‰ | | 138 | 8A | Š | | 139 | 8B | ‹ | | 140 | 8C | Œ | | 141 | 8D |  | | 142 | 8E | Ž | | 143 | 8F |  | | 144 | 90 |  | | 145 | 91 | ‘ | | 146 | 92 | ’ | | 147 | 93 | “ | | 148 | 94 | ” | | 149 | 95 | • | | 150 | 96 | – | | 151 | 97 | — | | 152 | 98 | ˜ | | 153 | 99 | ™ | | 154 | 9A | š | | 155 | 9B | › | | 156 | 9C | œ | | 157 | 9D |  | | 158 | 9E | ž | | 159 | 9F | Ÿ | | 160 | A0 | | | 161 | A1 | ¡ | | 162 | A2 | ¢ | | 163 | A3 | £ | | 164 | A4 | ¤ | | 165 | A5 | ¥ | | 166 | A6 | ¦ | | 167 | A7 | § | | 168 | A8 | ¨ | | 169 | A9 | © | | 170 | AA | ª | | 171 | AB | « | | 172 | AC | ¬ | | 173 | AD | ­ | | 174 | AE | ® | | 175 | AF | ¯ | | 176 | B0 | ° | | 177 | B1 | ± | | 178 | B2 | ² | | 179 | B3 | ³ | | 180 | B4 | ´ | | 181 | B5 | µ | | 182 | B6 | ¶ | | 183 | B7 | · | | 184 | B8 | ¸ | | 185 | B9 | ¹ | | 186 | BA | º | | 187 | BB | » | | 188 | BC | ¼ | | 189 | BD | ½ | | 190 | BE | ¾ | | 191 | BF | ¿ | | 192 | C0 | À | | 193 | C1 | Á | | 194 | C2 |  | | 195 | C3 | à | | 196 | C4 | Ä | | 197 | C5 | Å | | 198 | C6 | Æ | | 199 | C7 | Ç | | 200 | C8 | È | | 201 | C9 | É | | 202 | CA | Ê | | 203 | CB | Ë | | 204 | CC | Ì | | 205 | CD | Í | | 206 | CE | Î | | 207 | CF | Ï | | 208 | D0 | Ð | | 209 | D1 | Ñ | | 210 | D2 | Ò | | 211 | D3 | Ó | | 212 | D4 | Ô | | 213 | D5 | Õ | | 214 | D6 | Ö | | 215 | D7 | × | | 216 | D8 | Ø | | 217 | D9 | Ù | | 218 | DA | Ú | | 219 | DB | Û | | 220 | DC | Ü | | 221 | DD | Ý | | 222 | DE | Þ | | 223 | DF | ß | | 224 | E0 | à | | 225 | E1 | á | | 226 | E2 | â | | 227 | E3 | ã | | 228 | E4 | ä | | 229 | E5 | å | | 230 | E6 | æ | | 231 | E7 | ç | | 232 | E8 | è | | 233 | E9 | é | | 234 | EA | ê | | 235 | EB | ë | | 236 | EC | ì | | 237 | ED | í | | 238 | EE | î | | 239 | EF | ï | | 240 | F0 | ð | | 241 | F1 | ñ | | 242 | F2 | ò | | 243 | F3 | ó | | 244 | F4 | ô | | 245 | F5 | õ | | 246 | F6 | ö | | 247 | F7 | ÷ | | 248 | F8 | ø | | 249 | F9 | ù | | 250 | FA | ú | | 251 | FB | û | | 252 | FC | ü | | 253 | FD | ý | | 254 | FE | þ | | 255 | FF | ÿ |