diff --git a/doc/en/weechat_plugin_api.en.adoc b/doc/en/weechat_plugin_api.en.adoc
index 3c72ae974..a5cdf5e84 100644
--- a/doc/en/weechat_plugin_api.en.adoc
+++ b/doc/en/weechat_plugin_api.en.adoc
@@ -537,6 +537,55 @@ num_files = 2
 str = weechat.ngettext("file", "files", num_files)
 ----
 
+==== asprintf
+
+_WeeChat ≥ 4.3.0._
+
+Format a message in a string allocated by the function.
+
+[NOTE]
+This function is defined for systems where the GNU function `asprintf()`
+is not available. +
+The behavior is almost the same except that `*result` is set to NULL on error.
+
+Prototype:
+
+[source,c]
+----
+int weechat_asprintf (char **result, const char *fmt, ...);
+----
+
+Arguments:
+
+* _result_: pointer to a string pointer
+* _fmt_: format string
+
+Return value:
+
+* number of bytes written in `*result` (excluding the final null byte),
+  a negative value in case of error.
+
+C example:
+
+[source,c]
+----
+char *str;
+
+if (weechat_asprintf (&str, "%s, %d", "test", 42) >= 0)
+{
+    /* *str == "test, 42" */
+    /* ... */
+    free (str);
+}
+else
+{
+    /* error: *str == NULL */
+}
+----
+
+[NOTE]
+This function is not available in scripting API.
+
 ==== strndup
 
 Return duplicated string, with a max number of bytes.
diff --git a/doc/fr/weechat_plugin_api.fr.adoc b/doc/fr/weechat_plugin_api.fr.adoc
index 36937541e..ea4acd4e5 100644
--- a/doc/fr/weechat_plugin_api.fr.adoc
+++ b/doc/fr/weechat_plugin_api.fr.adoc
@@ -547,6 +547,56 @@ num_files = 2
 str = weechat.ngettext("file", "files", num_files)
 ----
 
+==== asprintf
+
+_WeeChat ≥ 4.3.0._
+
+Formater un message dans une chaîne allouée par la fonction.
+
+[NOTE]
+Cette fonction est définie pour les systèmes où la fonction GNU `asprintf()`
+n'est pas disponible. +
+Le comportement est quasiment le même à l'exception de `*result` qui est mis à
+NULL en cas d'erreur.
+
+Prototype :
+
+[source,c]
+----
+int weechat_asprintf (char **result, const char *fmt, ...);
+----
+
+Paramètres :
+
+* _result_ : pointeur vers un pointeur de chaîne
+* _fmt_ : chaîne de formatage
+
+Valeur de retour :
+
+* nombre d'octets écrits dans `*result` (en excluant le caractère nul de fin),
+  une valeur négative en cas d'erreur.
+
+Exemple en C :
+
+[source,c]
+----
+char *str;
+
+if (weechat_asprintf (&str, "%s, %d", "test", 42) >= 0)
+{
+    /* *str == "test, 42" */
+    /* ... */
+    free (str);
+}
+else
+{
+    /* erreur : *str == NULL */
+}
+----
+
+[NOTE]
+Cette fonction n'est pas disponible dans l'API script.
+
 ==== strndup
 
 Retourner la chaîne dupliquée, avec un nombre maximum d'octets.
diff --git a/doc/it/weechat_plugin_api.it.adoc b/doc/it/weechat_plugin_api.it.adoc
index 7ee9cc055..a3fcab585 100644
--- a/doc/it/weechat_plugin_api.it.adoc
+++ b/doc/it/weechat_plugin_api.it.adoc
@@ -568,6 +568,60 @@ num_files = 2
 str = weechat.ngettext("file", "files", num_files)
 ----
 
+==== asprintf
+
+_WeeChat ≥ 4.3.0._
+
+// TRANSLATION MISSING
+Format a message in a string allocated by the function.
+
+// TRANSLATION MISSING
+[NOTE]
+This function is defined for systems where the GNU function `asprintf()`
+is not available. +
+The behavior is almost the same except that `*result` is set to NULL on error.
+
+Prototipo:
+
+[source,c]
+----
+int weechat_asprintf (char **result, const char *fmt, ...);
+----
+
+Argomenti:
+
+// TRANSLATION MISSING
+* _result_: pointer to a string pointer
+// TRANSLATION MISSING
+* _fmt_: format string
+
+Valore restituito:
+
+// TRANSLATION MISSING
+* number of bytes written in `*result` (excluding the final null byte),
+  a negative value in case of error.
+
+Esempio in C:
+
+[source,c]
+----
+char *str;
+
+if (weechat_asprintf (&str, "%s, %d", "test", 42) >= 0)
+{
+    /* *str == "test, 42" */
+    /* ... */
+    free (str);
+}
+else
+{
+    /* error: *str == NULL */
+}
+----
+
+[NOTE]
+Questa funzione non è disponibile nelle API per lo scripting.
+
 ==== strndup
 
 // TRANSLATION MISSING
diff --git a/doc/ja/weechat_plugin_api.ja.adoc b/doc/ja/weechat_plugin_api.ja.adoc
index 9bc90793f..a38b6fd95 100644
--- a/doc/ja/weechat_plugin_api.ja.adoc
+++ b/doc/ja/weechat_plugin_api.ja.adoc
@@ -547,6 +547,60 @@ num_files = 2
 str = weechat.ngettext("file", "files", num_files)
 ----
 
+==== asprintf
+
+_WeeChat ≥ 4.3.0._
+
+// TRANSLATION MISSING
+Format a message in a string allocated by the function.
+
+// TRANSLATION MISSING
+[NOTE]
+This function is defined for systems where the GNU function `asprintf()`
+is not available. +
+The behavior is almost the same except that `*result` is set to NULL on error.
+
+プロトタイプ:
+
+[source,c]
+----
+int weechat_asprintf (char **result, const char *fmt, ...);
+----
+
+引数:
+
+// TRANSLATION MISSING
+* _result_: pointer to a string pointer
+// TRANSLATION MISSING
+* _fmt_: format string
+
+戻り値:
+
+// TRANSLATION MISSING
+* number of bytes written in `*result` (excluding the final null byte),
+  a negative value in case of error.
+
+C 言語での使用例:
+
+[source,c]
+----
+char *str;
+
+if (weechat_asprintf (&str, "%s, %d", "test", 42) >= 0)
+{
+    /* *str == "test, 42" */
+    /* ... */
+    free (str);
+}
+else
+{
+    /* error: *str == NULL */
+}
+----
+
+[NOTE]
+スクリプト API ではこの関数を利用できません。
+
 ==== strndup
 
 // TRANSLATION MISSING
diff --git a/doc/sr/weechat_plugin_api.sr.adoc b/doc/sr/weechat_plugin_api.sr.adoc
index bcde00a9e..456f478a7 100644
--- a/doc/sr/weechat_plugin_api.sr.adoc
+++ b/doc/sr/weechat_plugin_api.sr.adoc
@@ -512,6 +512,60 @@ num_files = 2
 str = weechat.ngettext("file", "files", num_files)
 ----
 
+==== asprintf
+
+_WeeChat ≥ 4.3.0._
+
+// TRANSLATION MISSING
+Format a message in a string allocated by the function.
+
+// TRANSLATION MISSING
+[NOTE]
+This function is defined for systems where the GNU function `asprintf()`
+is not available. +
+The behavior is almost the same except that `*result` is set to NULL on error.
+
+Прототип:
+
+[source,c]
+----
+int weechat_asprintf (char **result, const char *fmt, ...);
+----
+
+Аргументи:
+
+// TRANSLATION MISSING
+* _result_: pointer to a string pointer
+// TRANSLATION MISSING
+* _fmt_: format string
+
+Повратна вредност:
+
+// TRANSLATION MISSING
+* number of bytes written in `*result` (excluding the final null byte),
+  a negative value in case of error.
+
+C пример:
+
+[source,c]
+----
+char *str;
+
+if (weechat_asprintf (&str, "%s, %d", "test", 42) >= 0)
+{
+    /* *str == "test, 42" */
+    /* ... */
+    free (str);
+}
+else
+{
+    /* error: *str == NULL */
+}
+----
+
+[NOTE]
+Ова функција није доступна у API скриптовања.
+
 ==== strndup
 
 Враћа дуплирани стринг, са максималним бројем бајтова.
diff --git a/src/core/core-string.c b/src/core/core-string.c
index 572e6d1cd..4b8f3c957 100644
--- a/src/core/core-string.c
+++ b/src/core/core-string.c
@@ -70,6 +70,61 @@ int string_concat_index = 0;
 char **string_concat_buffer[STRING_NUM_CONCAT_BUFFERS];
 
 
+/*
+ * Formats a message in a string allocated by the function.
+ *
+ * This function is defined for systems where the GNU function `asprintf()`
+ * is not available.
+ * The behavior is almost the same except that `*result` is set to NULL on error.
+ *
+ * Returns the number of bytes in the resulting string, negative value in case
+ * of error.
+ *
+ * Value of `*result` is allocated with the result string (NULL if error),
+ * it must be freed after use.
+ */
+
+int
+string_asprintf (char **result, const char *fmt, ...)
+{
+    va_list argptr;
+    int num_bytes;
+    size_t size;
+
+    if (!result)
+        return -1;
+
+    *result = NULL;
+
+    if (!fmt)
+        return -1;
+
+    /* determine required size */
+    va_start (argptr, fmt);
+    num_bytes = vsnprintf (NULL, 0, fmt, argptr);
+    va_end (argptr);
+
+    if (num_bytes < 0)
+        return num_bytes;
+
+    size = (size_t)num_bytes + 1;
+    *result = malloc (size);
+    if (!*result)
+        return -1;
+
+    va_start (argptr, fmt);
+    num_bytes = vsnprintf (*result, size, fmt, argptr);
+    va_end (argptr);
+
+    if (num_bytes < 0)
+    {
+        free (*result);
+        *result = NULL;
+    }
+
+    return num_bytes;
+}
+
 /*
  * Defines a "strndup" function for systems where this function does not exist
  * (FreeBSD and maybe others).
diff --git a/src/core/core-string.h b/src/core/core-string.h
index e79ce6279..6408114f2 100644
--- a/src/core/core-string.h
+++ b/src/core/core-string.h
@@ -39,6 +39,7 @@ struct t_string_dyn
 
 struct t_hashtable;
 
+extern int string_asprintf (char **result, const char *fmt, ...);
 extern char *string_strndup (const char *string, int bytes);
 extern char *string_cut (const char *string, int length, int count_suffix,
                          int screen, const char *cut_suffix);
diff --git a/src/plugins/plugin.c b/src/plugins/plugin.c
index 90227fd25..d885774b8 100644
--- a/src/plugins/plugin.c
+++ b/src/plugins/plugin.c
@@ -608,6 +608,7 @@ plugin_load (const char *filename, int init_plugin, int argc, char **argv)
         new_plugin->iconv_from_internal = &string_iconv_from_internal;
         new_plugin->gettext = &plugin_api_gettext;
         new_plugin->ngettext = &plugin_api_ngettext;
+        new_plugin->asprintf = &string_asprintf;
         new_plugin->strndup = &string_strndup;
         new_plugin->string_cut = &string_cut;
         new_plugin->string_tolower = &string_tolower;
diff --git a/src/plugins/weechat-plugin.h b/src/plugins/weechat-plugin.h
index c71313545..052ccb90c 100644
--- a/src/plugins/weechat-plugin.h
+++ b/src/plugins/weechat-plugin.h
@@ -73,7 +73,7 @@ struct t_weelist_item;
  * please change the date with current one; for a second change at same
  * date, increment the 01, otherwise please keep 01.
  */
-#define WEECHAT_PLUGIN_API_VERSION "20240307-01"
+#define WEECHAT_PLUGIN_API_VERSION "20240402-01"
 
 /* macros for defining plugin infos */
 #define WEECHAT_PLUGIN_NAME(__name)                                     \
@@ -316,6 +316,7 @@ struct t_weechat_plugin
     char *(*iconv_from_internal) (const char *charset, const char *string);
     const char *(*gettext) (const char *string);
     const char *(*ngettext) (const char *single, const char *plural, int count);
+    int (*asprintf) (char **result, const char *fmt, ...);
     char *(*strndup) (const char *string, int bytes);
     char *(*string_cut) (const char *string, int length, int count_suffix,
                          int screen, const char *cut_suffix);
@@ -1290,7 +1291,9 @@ extern int weechat_plugin_end (struct t_weechat_plugin *plugin);
 #define weechat_gettext(string) (weechat_plugin->gettext)(string)
 #define weechat_ngettext(single,plural,number)                          \
     (weechat_plugin->ngettext)(single, plural, number)
-#define weechat_strndup(__string, __bytes)                              \
+#define weechat_asprintf(__result, __fmt, __argz...)                    \
+    (weechat_plugin->asprintf)(__result, __fmt, ##__argz)
+#define weechat_strndup(__string, __bytes)              \
     (weechat_plugin->strndup)(__string, __bytes)
 #define weechat_string_cut(__string, __length, __count_suffix,          \
                            __screen, __cut_suffix)                      \
diff --git a/tests/unit/core/test-core-string.cpp b/tests/unit/core/test-core-string.cpp
index 8881d2df5..2d6552a31 100644
--- a/tests/unit/core/test-core-string.cpp
+++ b/tests/unit/core/test-core-string.cpp
@@ -123,6 +123,43 @@ TEST_GROUP(CoreString)
 {
 };
 
+/*
+ * Tests functions:
+ *   string_asprintf
+ */
+
+TEST(CoreString, Asprintf)
+{
+    char *test;
+
+    test = (char *)0x1;
+    LONGS_EQUAL(-1, string_asprintf (NULL, NULL));
+    POINTERS_EQUAL(0x1, test);
+
+    test = (char *)0x1;
+    LONGS_EQUAL(-1, string_asprintf (NULL, ""));
+    POINTERS_EQUAL(0x1, test);
+
+    test = (char *)0x1;
+    LONGS_EQUAL(-1, string_asprintf (&test, NULL));
+    POINTERS_EQUAL(NULL, test);
+
+    test = (char *)0x1;
+    LONGS_EQUAL(0, string_asprintf (&test, ""));
+    STRCMP_EQUAL("", test);
+    free (test);
+
+    test = (char *)0x1;
+    LONGS_EQUAL(4, string_asprintf (&test, "test"));
+    STRCMP_EQUAL("test", test);
+    free (test);
+
+    test = (char *)0x1;
+    LONGS_EQUAL(16, string_asprintf (&test, "test, %s, %d", "string", 42));
+    STRCMP_EQUAL("test, string, 42", test);
+    free (test);
+}
+
 /*
  * Tests functions:
  *   string_strndup