diff --git a/doc/api/addons.md b/doc/api/addons.md
index 1db1e5ecaf9d5b..bc3cf2d41f56a0 100644
--- a/doc/api/addons.md
+++ b/doc/api/addons.md
@@ -246,7 +246,7 @@ napi_value Method(napi_env env, napi_callback_info args) {
   napi_value greeting;
   napi_status status;
 
-  status = napi_create_string_utf8(env, "hello", 6, &greeting);
+  status = napi_create_string_utf8(env, "hello", NAPI_AUTO_LENGTH, &greeting);
   if (status != napi_ok) return nullptr;
   return greeting;
 }