IntelliJ IDEA recognizes numerous file types. Each file type is denoted with a special icon. Custom files types are also allowed. Each file type is associated with one or more extensions that match a certain pattern.

The file types and their extensions are configurable in the File Types dialog.

"Recognized" does not mean "supplied with extensive support". For example, php files are recognized in the Community Edition and marked with the corresponding icon, although the edition does not provide PHP development support.

The file recognized types depend on the installed plugins.

The default types include:

File TypeIconRecognized in
ActionScript files ActionScript files fileTypeActionScript.png

Ultimate Edition

Active Server Pages files fileTypeActiveServerPages.png Ultimate Edition
Android files ../../Shared/fileTypeAndroid.png Ultimate Edition: all Android-related file types;

Community Edition: Android IDL files, Android renderscript files
Apache Config files fileTypeApacheConfig.png Ultimate Edition
Archive files ../../Shared/icon_create_archive.png Ultimate Edition, Community Edition
AspectJ files fileTypeAspectJ.png Ultimate Edition, Community Edition
C# files../../Shared/fileTypeCSharp.pngUltimate Edition, Community Edition
C/C++ files../../Shared/fileTypeC.pngUltimate Edition, Community Edition
Command Shell files../../Shared/fileTypeCommandShell.pngUltimate Edition
CSS files ../../Shared/fileTypeCss.pngUltimate Edition
CoffeeScript files../../Shared/icon_CoffeeScript.pngUltimate Edition
Cucumber feature files../../Shared/fileTypeCucumber.pngUltimate Edition
ColdFusion files../../Shared/fileTypeColdFusion.pngUltimate Edition
Eclipse project files../../Shared/eclipseFile.pngUltimate Edition, Community Edition
Dart files../../Shared/icon_dart.pngUltimate Edition, Community Edition
Diagram files../../Shared/icon_UML.pngUltimate Edition
Drools files../../Shared/fileTypeDrools.pngUltimate Edition
Erlang files../../Shared/fileTypeC.pngUltimate Edition, Community Edition
EJB QL files../../Shared/fileTypeC.pngUltimate Edition, Community Edition
Files marked as plain text../../Shared/plain_text_icon.pngUltimate Edition, Community Edition
Files opened in associated applications../../Shared/iconFileTypeCustom.pngUltimate Edition, Community Edition
FreeMarker template files../../Shared/fileTypeFreeMarker.pngUltimate Edition
Gant scripts../../Shared/icon_gant.pngUltimate Edition
Gradle scripts../../Shared/icon_gradle.pngUltimate Edition
Groovy files../../Shared/fileTypeGroovy.pngUltimate Edition, Community Edition
Groovy Server Pages../../Shared/fileTypeGSP.pngUltimate Edition
GUI FormimgUltimate Edition, Community Edition
Handlebars files../../Shared/fileTypeHandlebars.pngUltimate Edition
HAML files ../../Shared/fileTypeHAML.pngUltimate Edition
HTML files ../../Shared/classTypeHtml.pngUltimate Edition, Community Edition
IntelliJ IDEA project, module or workspace files.../../Shared/ideaProjectFile.pngUltimate Edition, Community Edition
IDL files../../Shared/fileTypeIdl.pngUltimate Edition, Community Edition
Image files../../Shared/fileTypeImage.pngUltimate Edition, Community Edition
Java class files../../Shared/fileTypeJavaClass.pngUltimate Edition, Community Edition
Java source files../../Shared/fileTypeJavaSource.pngUltimate Edition, Community Edition
JavaFX files../../Shared/fileTypeC.pngUltimate Edition, Community Edition
JavaScript files../../Shared/fileTypeJavaScript.pngUltimate Edition
JavaScript test files../../Shared/fileTypeJSTest.pngUltimate Edition
JavaScript files that can be executed on Node.Js../../Shared/fileTypeJSFileToRunOnNode.pngUltimate Edition
Jade files (refer to the section Pug (Jade) Template Engine).../../Shared/jade.pngUltimate Edition
JSF files../../Shared/fileTypeJSF.pngUltimate Edition, Community Edition
JSHint configuration files ../../Shared/ac_iconJSHint.png Ultimate Edition
JSON files../../Shared/fileTypeJSON.pngUltimate Edition
JSTestDriver Config filesfileTypeJSTestDriverConfig.pngUltimate Edition
Java Server Pages files../../Shared/fileTypeJSP.pngUltimate Edition, Community Edition
JSPx files../../Shared/fileTypeJSPX.pngUltimate Edition, Community Edition
Kotlin files../../Shared/kotlin_file.pngUltimate Edition, Community Edition
Kotlin classes../../Shared/kotlin_class.pngUltimate Edition, Community Edition
Kotlin interfaces../../Shared/kotlin_file.pngUltimate Edition, Community Edition
Kotlin enums../../Shared/kotlin_enum.pngUltimate Edition, Community Edition
Kotlin objects../../Shared/kotlin_object.pngUltimate Edition, Community Edition
Less files ../../Shared/fileTypeLESS.pngUltimate Edition
Patch files../../Shared/patch.pngUltimate Edition, Community Edition
Perl files../../Shared/fileTypeJavaScript.pngUltimate Edition, Community Edition
PHP files ../../Shared/fileTypePHP.pngUltimate Edition, Community Edition
Properties files../../Shared/propertiesFile.pngUltimate Edition, Community Edition
Resource bundles../../Shared/resource_bundle_icon.pngUltimate Edition, Community Edition
XML-based properties files../../Shared/xml_properties_icon.pngUltimate Edition, Community Edition
Pug files (refer to the section Pug (Jade) Template Engine). ../../Shared/pug.pngUltimate Edition
Regular expressions../../Shared/fileTypeRegexp.pngUltimate Edition, Community Edition
RELAX NG Compact Syntax../../Shared/fileTypeRelaxNG.pngUltimate Edition, Community Edition
Sass files ../../Shared/fileTypeSASS.pngUltimate Edition
SCSS files ../../Shared/fileTypeSASS.pngUltimate Edition
Scala files../../Shared/scala_files.pngUltimate Edition
Smarty, Smarty config files ../../Shared/fileTypeSmarty.png Ultimate Edition
SQL files../../Shared/icon_sqlOpenInEditor.png Ultimate Edition, Community Edition
Stylus files../../Shared/fileTypeStylus.png Ultimate Edition
Drools Expert files../../Shared/fileTypeDrools.pngUltimate Edition
Text files../../Shared/ac_iconFileTypeText.png Ultimate Edition, Community Edition
TypeScript files ../../Shared/ac_iconFileType_TypeScript.png Ultimate Edition
Velocity template files../../Shared/fileTypeVelocity.png Ultimate Edition
XHTML files ../../Shared/ac_iconFileTypeXHTML.png Ultimate Edition, Community Edition
XML DTD files ../../Shared/ac_iconFileTypeDTD.png Ultimate Edition, Community Edition
XML files ../../Shared/ac_iconFileTypeXML.png Ultimate Edition, Community Edition
YAML files ../../Shared/fileTypeYAML.png Ultimate Edition