diff --git a/goldens/public-api/common/index.md b/goldens/public-api/common/index.md
index 4ee2eea8ca3..03d2494c13c 100644
--- a/goldens/public-api/common/index.md
+++ b/goldens/public-api/common/index.md
@@ -141,9 +141,9 @@ export class DatePipe implements PipeTransform {
 // @public
 export interface DatePipeConfig {
     // (undocumented)
-    dateFormat: string;
+    dateFormat?: string;
     // (undocumented)
-    timezone: string;
+    timezone?: string;
 }
 
 // @public
diff --git a/packages/common/src/pipes/date_pipe_config.ts b/packages/common/src/pipes/date_pipe_config.ts
index 54d15addba5..3ec75eff8ff 100644
--- a/packages/common/src/pipes/date_pipe_config.ts
+++ b/packages/common/src/pipes/date_pipe_config.ts
@@ -15,8 +15,8 @@
  * @publicApi
  */
 export interface DatePipeConfig {
-  dateFormat: string;
-  timezone: string;
+  dateFormat?: string;
+  timezone?: string;
 }
 
 /**