diff --git a/docs/doxygen/overviews/xrc_format.h b/docs/doxygen/overviews/xrc_format.h
index 4fbf46b86c..a23fba23d1 100644
--- a/docs/doxygen/overviews/xrc_format.h
+++ b/docs/doxygen/overviews/xrc_format.h
@@ -2674,14 +2674,15 @@ should be processed on. It is filtered out and ignored on any other platforms.
 
 Possible elemental values are:
 @beginDefList
-@itemdef{ @c win, Windows }
-@itemdef{ @c mac, macOS (or Mac Classic in wxWidgets version supporting it) }
+@itemdef{ @c msw, Windows, preferred platform name }
+@itemdef{ @c win, Windows, alternative synonym }
+@itemdef{ @c mac, macOS or iOS }
 @itemdef{ @c unix, Any Unix platform @em except macOS }
 @endDefList
 
 Examples:
 @code
-<label platform="win">Windows</label>
+<label platform="msw">Windows</label>
 <label platform="unix">Unix</label>
 <label platform="mac">macOS</label>
 <help platform="mac|unix">Not a Windows machine</help>
diff --git a/include/wx/platinfo.h b/include/wx/platinfo.h
index 863d94f51f..03c5dcc602 100644
--- a/include/wx/platinfo.h
+++ b/include/wx/platinfo.h
@@ -137,6 +137,40 @@ struct wxLinuxDistributionInfo
     { return !(*this == ldi); }
 };
 
+// Platform ID is a very broad platform categorization used in external files
+// (e.g. XRC), so the values here must remain stable and cannot be changed.
+class wxPlatformId
+{
+public:
+    // Returns the preferred current platform name, use MatchesCurrent() to
+    // check if the name is one of the possibly several names corresponding to
+    // the current platform.
+    static wxString GetCurrent()
+    {
+#ifdef __WINDOWS__
+        return wxASCII_STR("msw");
+#elif defined(__APPLE__)
+        return wxASCII_STR("mac");
+#elif defined(__UNIX__)
+        return wxASCII_STR("unix");
+#else
+        return wxString();
+#endif
+    }
+
+    // Returns true if the given string matches the current platform.
+    static bool MatchesCurrent(const wxString& s)
+    {
+        // Under MSW we also support "win" platform name for compatibility with
+        // the existing XRC files using it.
+#ifdef __WINDOWS__
+        if (s == wxASCII_STR("win"))
+            return true;
+#endif // __WINDOWS__
+
+        return s == GetCurrent();
+    }
+};
 
 // ----------------------------------------------------------------------------
 // wxPlatformInfo
diff --git a/interface/wx/platinfo.h b/interface/wx/platinfo.h
index 67cd046f97..1c37e09626 100644
--- a/interface/wx/platinfo.h
+++ b/interface/wx/platinfo.h
@@ -138,6 +138,45 @@ struct wxLinuxDistributionInfo
 };
 
 
+/**
+    @class wxPlatformId
+
+    Defines a very broad platform categorization.
+
+    Usually you would use wxPlatformInfo to get all the platform details rather
+    than this class which only distinguishes between MSW, Mac and Unix
+    platforms.
+
+    This class is mostly useful if a short string describing the platform
+    corresponds to the current platform, i.e. the platform under which the
+    executable runs. The recognized strings are:
+
+    - "msw" (preferred) or "win" (for compatibility) for MSW.
+    - "mac" for Apple systems, i.e. macOS and iOS.
+    - "unix" for the (other) Unix-like systems.
+
+    @since 3.1.5
+ */
+class wxPlatformId
+{
+    /**
+        Returns the preferred current platform name.
+
+        Use MatchesCurrent() to check if the name is one of the possibly
+        several names corresponding to the current platform.
+
+        Returns one of "msw", "mac" or "unix" or an empty string if the current
+        platform is not recognized.
+     */
+    static wxString GetCurrent();
+
+    /**
+        Returns true if the given string matches the current platform.
+     */
+    static bool MatchesCurrent(const wxString& s);
+};
+
+
 /**
     @class wxPlatformInfo
 
@@ -590,4 +629,3 @@ public:
 
     //@}
 };
-
diff --git a/src/xrc/xmlres.cpp b/src/xrc/xmlres.cpp
index 6b0d8d7a11..4ffeda9723 100644
--- a/src/xrc/xmlres.cpp
+++ b/src/xrc/xmlres.cpp
@@ -42,6 +42,7 @@
 #include "wx/hashset.h"
 #include "wx/scopedptr.h"
 #include "wx/config.h"
+#include "wx/platinfo.h"
 
 #include <limits.h>
 #include <locale.h>
@@ -585,15 +586,7 @@ static void ProcessPlatformProperty(wxXmlNode *node)
 
             while (tkn.HasMoreTokens())
             {
-                s = tkn.GetNextToken();
-#ifdef __WINDOWS__
-                if (s == wxT("win")) isok = true;
-#endif
-#if defined(__MAC__) || defined(__APPLE__)
-                if (s == wxT("mac")) isok = true;
-#elif defined(__UNIX__)
-                if (s == wxT("unix")) isok = true;
-#endif
+                isok = wxPlatformId::MatchesCurrent(tkn.GetNextToken());
 
                 if (isok)
                     break;