Questions tagged [ascii]

A character-encoding scheme based on the ordering of the English alphabet. ASCII stands for American Standard Code for Information Interchange.

ASCII codes represent text in computers, communications equipment, and other devices that use text. Most modern character-encoding schemes are based on ASCII, though they support many more characters than did ASCII.

ASCII includes definitions for 128 characters: 33 are non-printing control characters (now mostly obsolete) that affect how text and space is processed; 94 are printable characters, and the space is considered an invisible graphic. The most commonly used character encoding on the World Wide Web was US-ASCII until December 2007, when it was surpassed by UTF-8.

The following table contains the 128 ASCII characters.

Char  Dec  Oct Hex | Char Dec  Oct Hex | Char Dec  Oct Hex | Char Dec  Oct  Hex
(nul)   0 0000 x00 | (sp)  32 0040 x20 | @     64 0100 x40 | `      96 0140 x60
(soh)   1 0001 x01 | !     33 0041 x21 | A     65 0101 x41 | a      97 0141 x61
(stx)   2 0002 x02 | "     34 0042 x22 | B     66 0102 x42 | b      98 0142 x62
(etx)   3 0003 x03 | #     35 0043 x23 | C     67 0103 x43 | c      99 0143 x63
(eot)   4 0004 x04 | $     36 0044 x24 | D     68 0104 x44 | d     100 0144 x64
(enq)   5 0005 x05 | %     37 0045 x25 | E     69 0105 x45 | e     101 0145 x65
(ack)   6 0006 x06 | &     38 0046 x26 | F     70 0106 x46 | f     102 0146 x66
(bel)   7 0007 x07 | '     39 0047 x27 | G     71 0107 x47 | g     103 0147 x67
(bs)    8 0010 x08 | (     40 0050 x28 | H     72 0110 x48 | h     104 0150 x68
(ht)    9 0011 x09 | )     41 0051 x29 | I     73 0111 x49 | i     105 0151 x69
(nl)   10 0012 x0a | *     42 0052 x2a | J     74 0112 x4a | j     106 0152 x6a
(vt)   11 0013 x0b | +     43 0053 x2b | K     75 0113 x4b | k     107 0153 x6b
(np)   12 0014 x0c | ,     44 0054 x2c | L     76 0114 x4c | l     108 0154 x6c
(cr)   13 0015 x0d | -     45 0055 x2d | M     77 0115 x4d | m     109 0155 x6d
(so)   14 0016 x0e | .     46 0056 x2e | N     78 0116 x4e | n     110 0156 x6e
(si)   15 0017 x0f | /     47 0057 x2f | O     79 0117 x4f | o     111 0157 x6f
(dle)  16 0020 x10 | 0     48 0060 x30 | P     80 0120 x50 | p     112 0160 x70
(dc1)  17 0021 x11 | 1     49 0061 x31 | Q     81 0121 x51 | q     113 0161 x71
(dc2)  18 0022 x12 | 2     50 0062 x32 | R     82 0122 x52 | r     114 0162 x72
(dc3)  19 0023 x13 | 3     51 0063 x33 | S     83 0123 x53 | s     115 0163 x73
(dc4)  20 0024 x14 | 4     52 0064 x34 | T     84 0124 x54 | t     116 0164 x74
(nak)  21 0025 x15 | 5     53 0065 x35 | U     85 0125 x55 | u     117 0165 x75
(syn)  22 0026 x16 | 6     54 0066 x36 | V     86 0126 x56 | v     118 0166 x76
(etb)  23 0027 x17 | 7     55 0067 x37 | W     87 0127 x57 | w     119 0167 x77
(can)  24 0030 x18 | 8     56 0070 x38 | X     88 0130 x58 | x     120 0170 x78
(em)   25 0031 x19 | 9     57 0071 x39 | Y     89 0131 x59 | y     121 0171 x79
(sub)  26 0032 x1a | :     58 0072 x3a | Z     90 0132 x5a | z     122 0172 x7a
(esc)  27 0033 x1b | ;     59 0073 x3b | [     91 0133 x5b | {     123 0173 x7b
(fs)   28 0034 x1c | <     60 0074 x3c | \     92 0134 x5c | |     124 0174 x7c
(gs)   29 0035 x1d | =     61 0075 x3d | ]     93 0135 x5d | }     125 0175 x7d
(rs)   30 0036 x1e | >     62 0076 x3e | ^     94 0136 x5e | ~     126 0176 x7e
(us)   31 0037 x1f | ?     63 0077 x3f | _     95 0137 x5f | (del) 127 0177 x7f
6938 questions
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How to get the ASCII value of a character

How do I get the ASCII value of a character as an int in Python?
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Reading a plain text file in Java

It seems there are different ways to read and write data of files in Java. I want to read ASCII data from a file. What are the possible ways and their differences?
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What's the difference between ASCII and Unicode?

What's the exact difference between Unicode and ASCII? ASCII has a total of 128 characters (256 in the extended set). Is there any size specification for Unicode characters?
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Reminder - \r\n or \n\r?

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Why do we use Base64?

Wikipedia says Base64 encoding schemes are commonly used when there is a need to encode binary data that needs be stored and transferred over media that are designed to deal with textual data. This is to ensure that the data remains intact without…
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Unicode, UTF, ASCII, ANSI format differences

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Replace non-ASCII characters with a single space

I need to replace all non-ASCII (\x00-\x7F) characters with a space. I'm surprised that this is not dead-easy in Python, unless I'm missing something. The following function simply removes all non-ASCII characters: def remove_non_ascii_1(text): …
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How can you strip non-ASCII characters from a string? (in C#)
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What is ANSI format?

What is ANSI encoding format? Is it a system default format? In what way does it differ from ASCII?
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How to check if a string in Python is in ASCII?

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HTML code for an apostrophe

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Convert character to ASCII numeric value in java

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(grep) Regex to match non-ASCII characters?

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