diff --git a/src/zcl_mjs.clas.abap b/src/zcl_mjs.clas.abap
index 03ff738..3059041 100644
--- a/src/zcl_mjs.clas.abap
+++ b/src/zcl_mjs.clas.abap
@@ -2113,6 +2113,12 @@ CLASS zcl_mjs IMPLEMENTATION.
             rs_val = string_val( `boolean` ).
           WHEN 4.
             rs_val = string_val( `function` ).
+          WHEN 6.
+            IF ls_toval-obj->has( `__is_class__` ) = abap_true.
+              rs_val = string_val( `function` ).
+            ELSE.
+              rs_val = string_val( `object` ).
+            ENDIF.
           WHEN OTHERS.
             rs_val = string_val( `object` ).
         ENDCASE.
@@ -2262,6 +2268,7 @@ CLASS zcl_mjs IMPLEMENTATION.
           ENDIF.
           lo_cls_env->define( iv_name = `__super_proto__` is_val = ls_super_cls_val ).
         ENDIF.
+        ls_clsobj-obj->set( iv_key = `__is_class__` ir_val = box_value( bool_val( abap_true ) ) ).
         LOOP AT <n>-methods INTO DATA(ls_cm).
           DATA lr_mfn TYPE REF TO data.
           CREATE DATA lr_mfn TYPE zif_mjs=>ty_function.
diff --git a/src/zcl_mjs.clas.testclasses.abap b/src/zcl_mjs.clas.testclasses.abap
index b3676c9..0115618 100644
--- a/src/zcl_mjs.clas.testclasses.abap
+++ b/src/zcl_mjs.clas.testclasses.abap
@@ -100,6 +100,7 @@ CLASS ltcl_test DEFINITION FOR TESTING
     METHODS test_new_set FOR TESTING RAISING zcx_mjs_runtime.
     METHODS test_set_has FOR TESTING RAISING zcx_mjs_runtime.
     METHODS test_namespace_class FOR TESTING RAISING zcx_mjs_runtime.
+    METHODS test_class_typeof FOR TESTING RAISING zcx_mjs_runtime.
 
     METHODS test262 FOR TESTING RAISING zcx_mjs_runtime.
 
@@ -845,6 +846,16 @@ CLASS ltcl_test IMPLEMENTATION.
       exp = |true| ).
   ENDMETHOD.
 
+  METHOD test_class_typeof.
+    DATA(lv_nl) = cl_abap_char_utilities=>newline.
+    DATA(lv_js) =
+      `class MyClass {}` && lv_nl &&
+      `console.log(typeof MyClass);`.
+    cl_abap_unit_assert=>assert_equals(
+      act = trim( zcl_mjs=>eval( lv_js ) )
+      exp = |function| ).
+  ENDMETHOD.
+
   METHOD test262.
     DATA(lv_nl) = cl_abap_char_utilities=>newline.
     DATA(lv_js) =