Syntax Highlighting - Built-in Languages

Supported Programming Languages

Around 90 Programming Languages are supported by Notepad++:
ActionScript Ada ASN.1 ASP Assembly
AutoIt AviSynth BaanC Batch BlitzBasic
C C# C++ CAML CMake
COBOL CoffeeScript Csound CSS D
Diff Erlang ESCRIPT Forth Fortran fixed form
Fortran free form FreeBasic GDScript Go Gui4Cli
Haskell Hollywood HTML ini Inno Setup
Intel HEX Internal Search Java JavaScript json
json5 JSP KiXtart LaTeX Lisp
Lua Makefile MATLAB MMIXAL mssql
NFO Nim Nncrontab NSIS Objective-C
OScript Pascal Perl PHP PostScript
PowerShell Properties file PureBasic Python R
Raku RC REBOL registry Ruby
Rust S-Record Scheme Shell Smalltalk
Spice SQL Swift TCL Tektronix extended HEX
TeX txt2tags TypeScript Verilog VHDL
Visual Basic Visual Prolog XML YAML

For these languages, Notepad++ supports syntax highlighting (customizable), syntax folding, auto-completion (customizable), function list (customizable via PCRE in xml file).

If your beloved language is not in the list above, you can define it yourself easily, by using the User Defined Languages System. If that doesn’t meet your needs, you could write (or have someone else write) a lexer plugin.

Please note that in Notepad++ v8.3 and newer, Notepad++ has a feature will no longer perform syntax highlighting on files that are over 200MB – this prevents extreme performance slowdown caused by trying to syntax highlight extremely large files. This threshold is configurable in Settings > Preferences > Performance (starting in v8.4.7).

JavaScript

Internally, there are actually two entries for JavaScript: in the Style Configurator, these show up as “JavaScript” and “JavaScript (embedded)". The first is for standalone JavaScript files (usually with .js extension); the second is for when JavaScript is embedded in an HTML file – so you can actually have different color rules for when the JavaScript is inside HTML and when it’s a separate file. (In the langs.xml and stylers.xml config files, the standalone uses name="javascript.js".)

If you manually pick Language > J > JavaScript, the active file will use the standalone JavaScript settings.

Themes and Language Support

There are times when a particular Theme will not have been updated to include syntax highlighting for a given Language. If a Language you need is missing in your chosen Theme, you can open the %AppData%\Notepad++\themes\______.xml for your Theme, plus the C:\Program Files\Notepad++\stylers.model.xml (the locations of both those file can vary depending on your active Config Files Location for themes\______.xml, and your notepad++.exe executable’s directory for the stylers.model.xml, if you are not using a default installation). Search in stylers.model.xml for the <LexerType...> section for the missing Language, and copy that over to the appropriate location in your themes\______.xml. Close Notepad++ completely and re-run it: that Language should now be in the Style Configurator for your active theme, though depending on how different your Theme’s color scheme is compared to the Default Theme, the colors may be jarring compared to your Theme’s background color; but once it’s in the Style Configurator, you may update the color scheme for that Language in the Style Configurator. (If your Theme is a dark Theme, it might be better to copy from themes\DarkModeDefault.xml instead of copying from stylers.model.xml.)

Language Detection Priority

When opening an existing file, Notepad++ has an algorithm for trying to decide which language a given file is, with the following priorities:

  1. A language defined at the command line using -l is applied.
  2. If the file is in the active session file (the automatic session.xml or a manually-controlled session), it will use the language stored in that session.
  3. If the file extension is a “known extension” (whether it’s from the Style Configurator‘s default extension list [in langs.xml or langs.model.xml] or user-defined extension list [from stylers.xml or themes\<ThemeName>.xml] for a built-in language, or the User Defined Language‘s extension settings [from userDefineLang.xml or userDefineLangs\<UDLName>.xml]), Notepad++ will use that language.
  4. If the filename matches one of a few specific names, Notepad++ knows what language they should be:
    filename language
    makefile Makefile
    GNUMakefile Makefile
    CMakeLists.txt CMake
    SConstruct Python
    SConscript Python
    wscript Python
    Rakefile Ruby
    Vagrantfile Ruby
    crontab Shell Script
  5. If the first line in the file gives a known hint as to the file type, it will use that. This includes “prolog lines” starting with <?xml or <?php or <html or <!DOCTPE html or <?, or linux-style “shebang” lines like #!/usr/bin/bash which are looking for sh or python or perl or php or ruby or node to define the correct language.
  6. It will use the default language only if none of the other rules have matched.

As Notepad++ goes through that list in order, it will stop as soon as it finds a matching language for the file. And after Notepad++ has made its detection, you can override what it chose by using the Language menu (and when a session gets saved, the language will remember whatever language is currently active for that file for next time, as described in priority 2).

If you do a Save As on a file, it will use that same sequence for deciding the language, based on the new name and file contents.

Newly-created documents will assume the default language until they are saved.