diff --git a/Marlin/parser.h b/Marlin/parser.h
index 949c489cd0..88e46d2b71 100644
--- a/Marlin/parser.h
+++ b/Marlin/parser.h
@@ -93,6 +93,12 @@ public:
     void debug();
   #endif
 
+  GCodeParser() {
+    #if ENABLED(INCH_MODE_SUPPORT)
+      set_input_linear_units(LINEARUNIT_MM);
+    #endif
+  }
+
   // Reset is done before parsing
   static void reset();