diff --git a/packages/core/sdk/src/APIClient.ts b/packages/core/sdk/src/APIClient.ts
index dfe62112a..76acdf946 100644
--- a/packages/core/sdk/src/APIClient.ts
+++ b/packages/core/sdk/src/APIClient.ts
@@ -48,7 +48,7 @@ export class Auth {
   }
 
   initKeys() {
-    if (!window) {
+    if (typeof window === 'undefined') {
       return;
     }
     const appName = getSubAppName();