Unicode input

Decimal input

In some applications on Microsoft Windows, particularly those using the RichEdit control, decimal Unicode code points (for example, 256 for U+0100) are supported with Alt codes.

Unicode in HTML

HTML uses a different syntax for code points. Character codes may be specified after ampersand (&) and the number sign (#), and are followed by the semicolon (;). The number can be either in decimal or in hexadecimal. Preceding zeros may be omitted. If the input is in hexadecimal, the number is preceded by an "x". Some characters can also be used by "entity name".
Example: The HTML code of the copyright sign © (U+00A9) can be:
© (decimal input)
© (hexadecimal input)
© (entity name)

In Microsoft Windows

In order to enable a universal (independent of language settings) input method in Windows, one can add a string type (REG_SZ) value called EnableHexNumpad to the registry key HKEY_CURRENT_USER\Control Panel\Input Method and assign the value data 1 to it. Users need to log off/in on Windows 8.1/8.0, Windows 7, and Vista or reboot on earlier systems after editing the registry for this input method to start working. Unicode characters can then be entered by holding down Alt, pressing the + on the numeric keypad, followed by the hex code - using the numeric keypad for digits from 0 to 9 and letter keys for A to F digits - and then releasing Alt.^[2] This may not work for 5-digit hex codes like U+1F937.

UnicodeInput window

If, as on many laptops, the numeric keypad is unavailable, the utility UnicodeInput can be downloaded.^[3] If one invokes this program when typing text, the window shown on the right appears; to produce the desired character and make the window disappear, enter the hex value and press ↵ Enter.

AutoHotkey scripts support substitution of Unicode characters for keystrokes. For example, the command Send {U+2014} will insert an em dash in a text field in the active window.^[4]

Some individual Windows programs or apps already support the input of Unicode. For instance, WordPad and LibreOffice programs (Writer, Calc, etc.) support the following input method: one first enters the character’s hexadecimal code (between two and six hexadecimal digits), then immediately presses Alt+x. For example, entering f1 and then pressing the combination will produce the character ñ. Unless it is six hexadecimal digits long, the code must not be preceded by any digit or letters a–f as they will be treated as part of the code to be converted. For example, entering af1 followed by Alt+x will produce ૱ (U+0AF1), but entering a0000f1 followed by Alt+x will produce a ñ. This also works in Microsoft Word 2002/2003 for Windows. In Microsoft Word 2007/2010 for Windows Alt+c has to be used.

In macOS

In macOS the "Emoji & Symbols" (⌘ Command+Ctrl+Space) menu can be found in the Edit menu in many programs. This brings up the Characters palette allowing the user to choose any character from a variety of views. The user can then also search for the character or Unicode plane by name.^[5] In Mac OS 8.5 and later: one chooses the Unicode Hex Input keyboard layout; in OS X Yosemite, this can be added in Keyboard→Input Sources. Holding down the ⌥ Option, one then types the four-digit hex Unicode code point and the equivalent character appears. One can then release the ⌥ Option key.^[6] Characters outside of the BMP exceed the four-digit limit of the Unicode hex input mechanism but can be entered using the search entry box in the Character Viewer (Edit → Emoji & Symbols) or by using surrogate pairs.^[7] To use surrogate pairs, hold down the ⌥ Option key, the first surrogate, the + key (shift key is ignored), the second surrogate and then release the Option key.

In X11 (Linux and Unix variants)

The possibility of hexadecimal code input on operating systems using the X Window System depends on the system and applications. Hex input is not implemented in the common X.Org Server.^[8] Individual input methods and GUI toolkits can provide hex input independent of the X server.

For example, GTK+ is an ISO/IEC 14755-conformant system. The beginning sequence is Ctrl+⇧ Shift+U and the ending sequence is ↵ Enter or Space. Programs based on GTK+, such as GNOME applications, support Unicode input.

There are two common methods for direct input of Unicode characters:

• Hold Ctrl+⇧ Shift and type u followed by the hex digits. Then release Ctrl+⇧ Shift.
• Enter Ctrl+⇧ Shift+u, release, then type the hex digits, and press ↵ Enter (or Space or even on some systems, press and release ⇧ Shift or Ctrl ).

In non-GTK applications, however, there usually is no escape sequence to input arbitrary input characters. For example, Qt and KDE rely on the standard X Input Method (XIM) framework, and do not implement their own solutions.^[9] In xterm, these input methods are not supported, but using escape sequences is an alternative. rxvt-unicode implements optional ISO/IEC 14755, enabled by default.

However, regardless of the toolkit used, the Compose key subsystem can be used to configure certain key stroke combinations to input a subset of unicode.

In platform-independent applications

• In Emacs, Ctrl+x8↵ Enter or Meta+xinsert-char.
• In LibreOffice 5.1 onwards, type the hexadecimal number of a symbol and press Alt+X.
• In Opera versions that use the Presto layout engine—i.e. up to and including version 12.xx—, enter the hexadecimal number of the desired symbol or character and then press Ctrl+⇧ Shift+x (alternative shortcut Meta+⇧ Shift++x on macOS).
• In the Vim editor, in insert mode, the user first types Ctrl+V u (for codepoints up to 4 hex digits long; use Ctrl+V ⇧ Shift+U for longer), then types in the hexadecimal number of the symbol or character desired, and it will be converted into the symbol. (On Microsoft Windows, Ctrl+Q may be required instead of Ctrl+V.^[10])

The capability of Vim to create custom mnemonics, as described below, which could be employed on an ad-hoc basis, requires the decimal code point.