diff --git a/src/libecmaoperations/ecma-magic-strings.c b/src/libecmaoperations/ecma-magic-strings.c
index e55d2b582..99fe15298 100644
--- a/src/libecmaoperations/ecma-magic-strings.c
+++ b/src/libecmaoperations/ecma-magic-strings.c
@@ -53,6 +53,7 @@ ecma_get_magic_string_zt (ecma_magic_string_id_t id) /**< magic string id */
     case ECMA_MAGIC_STRING_LENGTH: return (ecma_char_t*) "length";
     case ECMA_MAGIC_STRING_NAN: return (ecma_char_t*) "NaN";
     case ECMA_MAGIC_STRING_INFINITY: return (ecma_char_t*) "Infinity";
+    case ECMA_MAGIC_STRING__COUNT: break;
   }
 
   JERRY_UNREACHABLE();
@@ -69,6 +70,37 @@ ecma_get_magic_string (ecma_magic_string_id_t id) /**< magic string id */
   return ecma_new_ecma_string (ecma_get_magic_string_zt (id));
 } /* ecma_get_magic_string */
 
+/**
+ * Check if passed string equals to one of magic strings
+ * and if equal magic string was found, return it's id in 'out_id_p' argument.
+ *
+ * @return true - if magic string equal to passed string was found,
+ *         false - otherwise.
+ */
+bool
+ecma_is_magic_string (ecma_char_t *zt_string_p, /**< zero-terminated string */
+                      ecma_magic_string_id_t *out_id_p) /**< out: magic string's id */
+{
+  TODO (Improve performance of search);
+
+
+  for (ecma_magic_string_id_t id = 0;
+       id < ECMA_MAGIC_STRING__COUNT;
+       id++)
+  {
+    if (ecma_compare_zt_strings (zt_string_p, ecma_get_magic_string_zt (id)))
+    {
+      *out_id_p = id;
+      
+      return true;
+    }
+  }
+
+  *out_id_p = ECMA_MAGIC_STRING__COUNT;
+
+  return false;
+} /* ecma_is_magic_string */
+
 /**
  * @}
  * @}
diff --git a/src/libecmaoperations/ecma-magic-strings.h b/src/libecmaoperations/ecma-magic-strings.h
index 4c6491291..922fa7154 100644
--- a/src/libecmaoperations/ecma-magic-strings.h
+++ b/src/libecmaoperations/ecma-magic-strings.h
@@ -46,11 +46,13 @@ typedef enum
   ECMA_MAGIC_STRING_FUNCTION, /**< "function" */
   ECMA_MAGIC_STRING_LENGTH, /**< "length" */
   ECMA_MAGIC_STRING_NAN, /**< "NaN" */
-  ECMA_MAGIC_STRING_INFINITY /**< "Infinity" */
+  ECMA_MAGIC_STRING_INFINITY, /**< "Infinity" */
+  ECMA_MAGIC_STRING__COUNT /**< number of magic strings */
 } ecma_magic_string_id_t;
 
 extern const ecma_char_t* ecma_get_magic_string_zt (ecma_magic_string_id_t id);
 extern ecma_string_t* ecma_get_magic_string (ecma_magic_string_id_t id);
+extern bool ecma_is_magic_string (ecma_char_t *zt_string_p, ecma_magic_string_id_t *out_id_p);
 
 /**
  * @}