diff --git a/support/hololens/ServoApp/BrowserPage.cpp b/support/hololens/ServoApp/BrowserPage.cpp
index 136490bab631..e4f460d34973 100644
--- a/support/hololens/ServoApp/BrowserPage.cpp
+++ b/support/hololens/ServoApp/BrowserPage.cpp
@@ -335,6 +335,15 @@ void BrowserPage::OnDevtoolsButtonClicked(IInspectable const &,
   }
 }
 
+void BrowserPage::OnJSInputEdited(IInspectable const &,
+                                  Input::KeyRoutedEventArgs const &e) {
+  if (e.Key() == Windows::System::VirtualKey::Enter) {
+    auto input = JSInput().Text();
+    JSInput().Text(L"");
+    mDevtoolsClient->Evaluate(input);
+  }
+}
+
 void BrowserPage::OnURLEdited(IInspectable const &,
                               Input::KeyRoutedEventArgs const &e) {
   if (e.Key() == Windows::System::VirtualKey::Enter) {
diff --git a/support/hololens/ServoApp/BrowserPage.h b/support/hololens/ServoApp/BrowserPage.h
index 048e39a6f1ab..454baee90765 100644
--- a/support/hololens/ServoApp/BrowserPage.h
+++ b/support/hololens/ServoApp/BrowserPage.h
@@ -30,6 +30,7 @@ struct BrowserPage : BrowserPageT<BrowserPage>, public servo::DevtoolsDelegate {
   void OnStopButtonClicked(IInspectable const &, RoutedEventArgs const &);
   void OnHomeButtonClicked(IInspectable const &, RoutedEventArgs const &);
   void OnDevtoolsButtonClicked(IInspectable const &, RoutedEventArgs const &);
+  void OnJSInputEdited(IInspectable const &, Input::KeyRoutedEventArgs const &);
   void OnURLEdited(IInspectable const &, Input::KeyRoutedEventArgs const &);
   void OnURLFocused(IInspectable const &);
   void
diff --git a/support/hololens/ServoApp/BrowserPage.xaml b/support/hololens/ServoApp/BrowserPage.xaml
index e9f4f18c5e35..7f1f051a4445 100644
--- a/support/hololens/ServoApp/BrowserPage.xaml
+++ b/support/hololens/ServoApp/BrowserPage.xaml
@@ -150,34 +150,41 @@
                 </Grid>
             </muxc:TabView.TabStripFooter>
             <muxc:TabViewItem x:Uid="devtoolsTabConsole" IsClosable="False">
-                <ListView ItemsSource="{x:Bind ConsoleLogs}">
-                    <ListView.ItemsPanel>
-                        <ItemsPanelTemplate>
-                            <ItemsStackPanel Orientation="Vertical" ItemsUpdatingScrollMode="KeepLastItemInView"/>
-                        </ItemsPanelTemplate>
-                    </ListView.ItemsPanel>
-                    <ListView.ItemTemplate>
-                        <DataTemplate x:DataType="local:ConsoleLog">
-                            <Grid Background="{x:Bind BgColor}" Padding="2">
-                                <Grid.ColumnDefinitions>
-                                    <ColumnDefinition Width="Auto"/>
-                                    <ColumnDefinition Width="*"/>
-                                    <ColumnDefinition Width="Auto"/>
-                                </Grid.ColumnDefinitions>
-                                <Ellipse Width="8" Height="8" Fill="{x:Bind FgColor}" Grid.Column="0" Margin="10,0"/>
-                                <TextBlock FontSize="12" Text="{x:Bind Body}"  Grid.Column="1"/>
-                                <TextBlock FontSize="12" Text="{x:Bind Source}" Foreground="Gray" Grid.Column="2" Margin="10,0"/>
-                            </Grid>
-                        </DataTemplate>
-                    </ListView.ItemTemplate>
-                    <ListView.ItemContainerStyle>
-                        <Style TargetType="ListViewItem">
-                            <Setter Property="Padding" Value="0"/>
-                            <Setter Property="MinHeight" Value="0"/>
-                            <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
-                        </Style>
-                    </ListView.ItemContainerStyle>
-                </ListView>
+                <Grid>
+                    <Grid.RowDefinitions>
+                        <RowDefinition Height="*"/>
+                        <RowDefinition Height="Auto"/>
+                    </Grid.RowDefinitions>
+                    <ListView ItemsSource="{x:Bind ConsoleLogs}">
+                        <ListView.ItemsPanel>
+                            <ItemsPanelTemplate>
+                                <ItemsStackPanel Orientation="Vertical" ItemsUpdatingScrollMode="KeepLastItemInView"/>
+                            </ItemsPanelTemplate>
+                        </ListView.ItemsPanel>
+                        <ListView.ItemTemplate>
+                            <DataTemplate x:DataType="local:ConsoleLog">
+                                <Grid Background="{x:Bind BgColor}" Padding="2">
+                                    <Grid.ColumnDefinitions>
+                                        <ColumnDefinition Width="Auto"/>
+                                        <ColumnDefinition Width="*"/>
+                                        <ColumnDefinition Width="Auto"/>
+                                    </Grid.ColumnDefinitions>
+                                    <Ellipse Width="8" Height="8" Fill="{x:Bind FgColor}" Grid.Column="0" Margin="10,0"/>
+                                    <TextBlock FontFamily="Consolas" FontSize="12" Text="{x:Bind Body}"  Grid.Column="1"/>
+                                    <TextBlock FontFamily="Consolas" FontSize="12" Text="{x:Bind Source}" Foreground="Gray" Grid.Column="2" Margin="10,0"/>
+                                </Grid>
+                            </DataTemplate>
+                        </ListView.ItemTemplate>
+                        <ListView.ItemContainerStyle>
+                            <Style TargetType="ListViewItem">
+                                <Setter Property="Padding" Value="0"/>
+                                <Setter Property="MinHeight" Value="0"/>
+                                <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
+                            </Style>
+                        </ListView.ItemContainerStyle>
+                    </ListView>
+                    <TextBox MinHeight="12" FontFamily="Consolas" FontSize="12" Grid.Row="1" IsTabStop="true" x:Name="JSInput" VerticalAlignment="Center" KeyUp="OnJSInputEdited" IsSpellCheckEnabled="False"/>
+                </Grid>
             </muxc:TabViewItem>
             <muxc:TabViewItem x:Uid="devtoolsTabServer" IsClosable="False">
                 <TextBlock x:Name="DevtoolsStatusMessage" Margin="10"></TextBlock>
diff --git a/support/hololens/ServoApp/Devtools/Client.cpp b/support/hololens/ServoApp/Devtools/Client.cpp
index c7d1b7cfc897..65fb51df892c 100644
--- a/support/hololens/ServoApp/Devtools/Client.cpp
+++ b/support/hololens/ServoApp/Devtools/Client.cpp
@@ -42,6 +42,16 @@ void DevtoolsClient::Run() {
   });
 }
 
+void DevtoolsClient::Evaluate(hstring code) {
+  if (!code.empty() && mConsoleActor.has_value()) {
+    JsonObject out;
+    out.Insert(L"to", *mConsoleActor);
+    out.Insert(L"type", JsonValue::CreateStringValue(L"evaluateJSAsync"));
+    out.Insert(L"text", JsonValue::CreateStringValue(code));
+    Send(out);
+  }
+}
+
 IAsyncAction DevtoolsClient::Loop() {
   auto cancellation = co_await winrt::get_cancellation_token();
   cancellation.callback([=] {
@@ -101,11 +111,12 @@ void DevtoolsClient::HandleMessage(JsonObject obj) {
       if (tab.HasKey(L"actor")) {
         // Attach to tab, and ask for cached messaged
         JsonObject msg1;
+        mConsoleActor = tab.GetNamedValue(L"consoleActor");
         msg1.Insert(L"to", tab.GetNamedValue(L"actor"));
         msg1.Insert(L"type", JsonValue::CreateStringValue(L"attach"));
         Send(msg1);
         JsonObject msg2;
-        msg2.Insert(L"to", tab.GetNamedValue(L"consoleActor"));
+        msg2.Insert(L"to", *mConsoleActor);
         msg2.Insert(L"type",
                     JsonValue::CreateStringValue(L"getCachedMessages"));
         JsonArray types;
@@ -116,6 +127,12 @@ void DevtoolsClient::HandleMessage(JsonObject obj) {
         return;
       }
     }
+  } else if (obj.HasKey(L"resultID")) {
+    // evaluateJSAsync response.
+    if (obj.GetNamedString(L"type", L"") == L"evaluationResult") {
+      HandleEvaluationResult(obj);
+    }
+    return;
   } else if (obj.HasKey(L"type")) { // Not from root
     if (obj.GetNamedString(L"type") == L"pageError") {
       // Got a page error
@@ -196,6 +213,29 @@ void DevtoolsClient::HandlePageError(JsonObject message) {
   mDelegate.OnDevtoolsMessage(level, source, body);
 }
 
+void DevtoolsClient::HandleEvaluationResult(JsonObject message) {
+  auto level = DevtoolsMessageLevel::None;
+  hstring body = L"";
+  if (message.HasKey(L"result")) {
+    auto value = message.GetNamedValue(L"result");
+    if (value.ValueType() == JsonValueType::Object) {
+      auto type = value.GetObject().GetNamedString(L"type");
+      if (type == L"undefined") {
+        body = L"undefined";
+      } else {
+        body = L"<object>";
+      }
+    } else {
+      body = value.Stringify();
+    }
+  } else if (message.GetNamedValue(L"exception").ValueType() !=
+             JsonValueType::Null) {
+    level = DevtoolsMessageLevel::Error;
+    body = message.GetNamedString(L"exceptionMessage", L"");
+  }
+  mDelegate.OnDevtoolsMessage(level, L"", body);
+}
+
 void DevtoolsClient::HandleConsoleMessage(JsonObject message) {
   auto source = ParseSource(message);
   auto level = ParseLevel(message);
diff --git a/support/hololens/ServoApp/Devtools/Client.h b/support/hololens/ServoApp/Devtools/Client.h
index 3764c201d46b..67e11c3fe795 100644
--- a/support/hololens/ServoApp/Devtools/Client.h
+++ b/support/hololens/ServoApp/Devtools/Client.h
@@ -26,6 +26,7 @@ class DevtoolsClient {
   void Run();
   void Stop();
   void Send(JsonObject);
+  void Evaluate(hstring);
 
 private:
   hstring mPort;
@@ -46,6 +47,8 @@ class DevtoolsClient {
   void HandlePageError(JsonObject);
   void HandleConsoleMessage(JsonObject);
   void HandleNonHandledMessage(JsonObject);
+  void HandleEvaluationResult(JsonObject);
+  std::optional<JsonValue> mConsoleActor;
 };
 
 class DevtoolsDelegate {