Add targets to generate or update Qt Linguist .ts files.

The command is defined in the LinguistTools component of the Qt6 package. Load the package with:

find_package(Qt6 REQUIRED COMPONENTS LinguistTools)

This command was introduced in Qt 6.2.


Since 6.7:

qt_add_lupdate(TS_FILES file1.ts [file2.ts ...]
               [PLURALS_TS_FILE file.ts]
               [SOURCE_TARGETS target1 [target2 ...]]
               [SOURCES source1.cpp [sources2.cpp ...]]
               [INCLUDE_DIRECTORIES directory1 [directory2 ...]]
               [LUPDATE_TARGET target-name]
               [OPTIONS ...])

Since 6.2 (deprecated):

qt_add_lupdate(target TS_FILES file1.ts [file2.ts ...]
               [SOURCES source1.cpp [sources2.cpp ...]]
               [INCLUDE_DIRECTORIES directory1 [directory2 ...]]
               [OPTIONS ...])

If versionless commands are disabled, use qt6_add_lupdate() instead. It supports the same set of arguments as this command.


Creates a custom target to generate or update Qt Linguist .ts files with lupdate.

The name of that custom target defaults to ${PROJECT_NAME}_lupdate. Further calls of qt_add_lupdate will create target names with an increasing number appended. The custom target name can be specified with the LUPDATE_TARGET option.

With the SOURCE_TARGETS argument you can specify a list of targets that contain sources with translatable strings. If SOURCE_TARGETS is not specified, you can specify SOURCES, which is described below. If neither SOURCE_TARGETS nor SOURCES is given, the command qt_collect_translation_source_targets is called to retrieve the list of targets.

The .ts files must be specified with the argument TS_FILES.

This function is designed to be used in conjunction with qt_add_lrelease. See also the convenience wrapper qt_add_translations.

Sources and Include Directories

With SOURCES you can explicitly specify additional source files that contain translatable strings.

You can use INCLUDE_DIRECTORIES to explicitly specify include directories for those source files.


You can set additional OPTIONS that should be passed when lupdate is invoked. You can find possible options in the lupdate documentation.

Umbrella Target

In addition to the target ${target}_lupdate, an umbrella target update_translations is created. This target will build all ${target}_lupdate targets that were created with qt_add_lupdate.

Pass NO_GLOBAL_TARGET to qt_add_lupdate to prevent this behavior.

The name of this target can be overridden by setting the variable QT_GLOBAL_LUPDATE_TARGET before calling qt_add_lupdate.

Plural Forms

QT_I18N_SOURCE_LANGUAGE specifies the language in which the source code strings are written. For handling plural forms correctly, create an additional .ts file for that language that only contains translatable strings for plural forms. See Handle Plural Forms for details.

With PLURALS_TS_FILE you can specify the .ts file for the source language. This file will only contain plural forms.

Deprecated Command Signature

Older versions of qt_add_lupdate took a target as the first argument. This is deprecated. Use the SOURCE_TARGETS argument instead.


Add the targets myapp_lupdate and update_translations for updating the .ts file of an application myapp.

    TS_FILES myapp_de.ts
    PLURALS_TS_FILE myapp_en.ts

You can specify the name of the created target by passing the LUPDATE_TARGET argument:

    LUPDATE_TARGET update_application_translations
    TS_FILES myapp_de.ts
    PLURALS_TS_FILE myapp_en.ts

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