diff --git a/docs/reference/initialization_config.mdx b/docs/reference/initialization_config.mdx
index 8fa159399..94048ad9c 100644
--- a/docs/reference/initialization_config.mdx
+++ b/docs/reference/initialization_config.mdx
@@ -481,7 +481,9 @@ This constructor is used to create an instance of Stagehand.
         </ResponseField>
       </Expandable>
     </ResponseField>
-    <ResponseField name="viewport" type="object">
+    <ResponseField name="viewport" type="object | null">
+      The size of the viewport. If set to `null`, the viewport will be set to the size of the operating system window. Defaults to `{ width: 1024, height: 768 }`.
+
       <Expandable title="properties">
         <ResponseField name="width" type="number">
           Width of the viewport.
diff --git a/lib/index.ts b/lib/index.ts
index 8e534ed87..f0c47d1d7 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -280,13 +280,19 @@ async function getBrowser(
     const context = await chromium.launchPersistentContext(userDataDir, {
       acceptDownloads: localBrowserLaunchOptions?.acceptDownloads ?? true,
       headless: localBrowserLaunchOptions?.headless ?? headless,
-      viewport: {
-        width: localBrowserLaunchOptions?.viewport?.width ?? 1024,
-        height: localBrowserLaunchOptions?.viewport?.height ?? 768,
-      },
+      viewport:
+        localBrowserLaunchOptions?.viewport === null
+          ? null
+          : {
+              width: localBrowserLaunchOptions?.viewport?.width ?? 1024,
+              height: localBrowserLaunchOptions?.viewport?.height ?? 768,
+            },
       locale: localBrowserLaunchOptions?.locale ?? "en-US",
       timezoneId: localBrowserLaunchOptions?.timezoneId ?? "America/New_York",
-      deviceScaleFactor: localBrowserLaunchOptions?.deviceScaleFactor ?? 1,
+      deviceScaleFactor:
+        localBrowserLaunchOptions?.viewport === null
+          ? undefined
+          : (localBrowserLaunchOptions?.deviceScaleFactor ?? 1),
       args: localBrowserLaunchOptions?.args ?? [
         "--disable-blink-features=AutomationControlled",
       ],
diff --git a/types/stagehand.ts b/types/stagehand.ts
index d6ed42d85..88b2d5e8a 100644
--- a/types/stagehand.ts
+++ b/types/stagehand.ts
@@ -198,7 +198,7 @@ export interface LocalBrowserLaunchOptions {
     urlFilter?: string | RegExp;
   };
   recordVideo?: { dir: string; size?: { width: number; height: number } };
-  viewport?: { width: number; height: number };
+  viewport?: { width: number; height: number } | null;
   deviceScaleFactor?: number;
   timezoneId?: string;
   bypassCSP?: boolean;