In PCs running the Microsoft Windows operating system, additional characters to those available by the current keyboard layout may be typed using the Alt key in conjunction with the keyboard's numeric pad. This technique is generally called Alt code. While being one of the first personal computers, the Altair 8800 was considered a mere toy due its lack of abilities. ... Microsoft Windows is the name of several families of proprietary software operating systems by Microsoft. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ... Computers and other typing devices offer many different keyboard layouts for inputting data in different languages. ... The term Alt codes is used to refer to a number of Unicode input methods that allow characters to be entered by typing a characters code point in concert with the Alt key. ...

The number typed and its resulting character correspond to two different character sets. A character encoding is a code that pairs a set of characters (such as an alphabet or syllabary) with a set of something else, such as numbers or electrical pulses. ...

• Without leading zero. If the number typed is not preceded by a zero, the character resulting from this number corresponds to code page 437 in the U.S. or code page 850 in Western Europe (also known as Multilingual (Latin-1)), which are Extended ASCII code pages, allowing 8-bit = 256 different characters. Most notably, this code page allows the input of graphical characters instead of the C0 control codes (values 1 - 31), such as {☺, ☻, ♥, ♦, ♣, ♠}, pressing Alt + {1, 2, 3, 4, 5, 6}, respectively (these characters can only be seen in the Windows GUI, not in the cmd.exe. For a full list of these graphical characters, see code page 437, for the remaining characters, see code page 850).
• With leading zero. If the number typed is preceded by a zero, the character resulting from this number corresponds to Windows-1252, another Extended ASCII code page, belonging to the group of Windows code pages, which are sometimes confusingly named Windows ANSI code pages. Most notably, this code page allows the input of C0 control codes, such as the {bell character, backspace, tab}, pressing Alt + {07, 08, 09}, respectively (for a full list of the typable characters, see Windows-1252).

As both character sets are based on the traditional 7-bit ASCII, the characters for values between 32 and 126 are the same. For values above 126, they mostly differ. IBM PC or MS-DOS code page 437, often abbreviated CP437 and also known as DOS-US or OEM-US, is the original character set of the IBM PC, circa 1981. ... The code page 850 is a code page which was used in occidental Europe, under systems such as DOS. It has been largely replaced with ISO 8859-1 and UTF-8, but is still sometimes used. ... The term extended ASCII (or high ASCII) describes eight-bit or larger character encodings that include the standard seven-bit ASCII characters as well as others. ... 8-bit refers to the number of bits used in the data bus of a computer. ... The C0 and C1 control code sets define control codes for use in text. ... A graphical user interface (GUI, often pronounced gooey) is a type of user interface which allows people to interact with a computer and computer-controlled devices which employ graphical icons, visual indicators or special graphical elements called widgets, along with text labels or text navigation to represent the information and... cmd. ... IBM PC or MS-DOS code page 437, often abbreviated CP437 and also known as DOS-US or OEM-US, is the original character set of the IBM PC, circa 1981. ... The code page 850 is a code page which was used in occidental Europe, under systems such as DOS. It has been largely replaced with ISO 8859-1 and UTF-8, but is still sometimes used. ... ISO 8859-1, more formally cited as ISO/IEC 8859-1 or less formally as Latin-1, is part 1 of ISO/IEC 8859, a standard character encoding defined by ISO. It encodes what it refers to as Latin alphabet no. ... There are 95 printable ASCII characters, numbered 32 to 126. ... Microsoft uses two main groups of code pages in Microsoft Windows (known as character encodings in other operating systems). ... The American National Standards Institute or ANSI (pronounced an-see) is a nonprofit organization that oversees the development of standards for products, services, processes and systems in the United States. ... Bell character is an ASCII control character, code 7 (^G). ... Backspace is the keyboard key that originally pushed the typewriter head one position backwards, and in modern computer displays moves the cursor one position backwards and deletes the preceding character. ... Tab (also spelled TaB) is a diet cola. ... ISO 8859-1, more formally cited as ISO/IEC 8859-1 or less formally as Latin-1, is part 1 of ISO/IEC 8859, a standard character encoding defined by ISO. It encodes what it refers to as Latin alphabet no. ... There are 95 printable ASCII characters, numbered 32 to 126. ...

Due to the character sets' ASCII basis and Microsoft's confusing policy of naming its character sets after ANSI, many people tend to name Windows Alt keycodes either ASCII codes or ANSI codes. The American National Standards Institute (ANSI) is a private, non-profit standards organization that produces industrial standards in the United States. ...

For values above 255, the value modulo 256 is used instead. E.g. typing Alt + 137 leads to ë, as does Alt + 393 (137 + 256). Typing Alt + 0137 leads to ‰, as does Alt + 02560137 (137 + 256 * 10000). In computing, the modulo operation finds the remainder of division of one number by another. ...

More examples

Code pages 850 use code point 151 for the lowercase u with grave accent (ù). Typing Alt+151 on a Windows machine will produce this character. When preferring Windows-1252 instead, one has to type Alt+0249 to get the same character, as 249 is character ù 's position in Windows-1252.

Table of characters (Alt Keycodes)

The pages linked from this article provide the list of characters indexed using hexadecimal numbers. In actual use, decimal numbers are required, as listed here. In mathematics and computer science, hexadecimal, base-16, or simply hex, is a numeral system with a radix, or base, of 16, usually written using the symbols 0–9 and A–F, or a–f. ...

N.D. = Not Defined in HTML 4 Standard. Dec = Decimal.
(Above) HTML code is compliant with ISO 10646, ISO 8879, ISO 8859-1.
Use (leading) "%" symbol before the hex code, to use it in the URL.
To use hex code in HTML, use HTML Hexadecimal code format, that is, use the x after the &#, for example, for cent sign (¢), use Ţ. The Universal Character Set is a character encoding that is defined by the international standard ISO/IEC 10646. ... The Standard Generalized Markup Language (SGML) is a metalanguage in which one can define markup languages for documents. ... ISO 8859-1, more formally cited as ISO/IEC 8859-1 or less formally as Latin-1, is part 1 of ISO/IEC 8859, a standard character encoding originally developed by ISO, but later jointly maintained by ISO and IEC. The standard, when supplemented with additional character assignments, is the...

Table of characters (Alt + X keycodes)

For characters which decimal equivalent code number is above 255, then the "Alt + Decimal_Equivalent_Number" keycodes will not work, for most characters, except few characters which are remapped below 256. For these characters we need to use the equivalent Hexadecimal code number. However, this does not apply in Microsoft Office Word XP or later. In mathematics and computer science, hexadecimal, base-16, or simply hex, is a numeral system with a radix, or base, of 16, usually written using the symbols 0–9 and A–F, or a–f. ...

To convert hexcodes into its equivalent symbol or character (existing in Unicode, or other Standard), another way is to use the Alt + X keys, after the hexcode is typed in the Word, Wordpad, etc software. Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. ...

Dec = Decimal.
Above chart is compliant with the Unicode "Latin Extended-A" block.
To use these char (Hex: 80 ~ 7FF) in URL, first convert each hex digit to its binary equivalent, then add binary 0 in front of it to make it (binary) 11 bits long, then insert binary "10" after the 5th binary bit, and insert binary "110" at the beginning, now make two groups of binary numbers, each containing 8 bits, by taking the first binary 8 bits and converting them to its hex equivalent, and convert rest of the binary 8 bits to its hex equivalent. Then use the "%" percent in front of these two groups to get the URL equivalent code. A Uniform Resource Locator, URL (spelled out as an acronym, not pronounced as earl), or Web address, is a standardized address name layout for resources (such as documents or images) on the Internet (or elsewhere). ...

(Above) HTML code is compliant with HTML 4.01, ISO 10646, ISO 8879, Latin extended A and B.
To use the hex code as HTML Hexadecimal, use the x after the &#, for example, for ohm sign (Ω), use Ω. In computing, HyperText Markup Language (HTML) is a markup language designed for the creation of web pages and other information viewable in a browser. ... The Universal Character Set is a character encoding that is defined by the international standard ISO/IEC 10646. ... The Standard Generalized Markup Language (SGML) is a metalanguage in which one can define markup languages for documents. ...

Reference charts

• Printable List of Alt Codes (UsefulShortcuts.Com)
• Windows Alt Key Codes (Penn State)
• Online Character Pickers (Richard Ishida, W3C)
• Keyboard Help - Learn how to create world language accent marks and other diacriticals on a computer