diff --git a/modules/juce_audio_processors/utilities/juce_ParameterAttachments.cpp b/modules/juce_audio_processors/utilities/juce_ParameterAttachments.cpp
index 0c2ca3e13406..1c516ba99b0b 100644
--- a/modules/juce_audio_processors/utilities/juce_ParameterAttachments.cpp
+++ b/modules/juce_audio_processors/utilities/juce_ParameterAttachments.cpp
@@ -310,7 +310,8 @@ void WebSliderParameterAttachment::sendInitialUpdate()
 
     object->setProperty ("numSteps", numSteps);
     object->setProperty ("interval", range.interval);
-    object->setProperty ("parameterIndex", parameter.getParameterIndex());
+    object->setProperty ("parameterIndex", parameter.getParameterIndex());
+    object->setProperty ("defaultValue", parameter.getDefaultValue());
     sliderState.emitEvent (object.get());
     attachment.sendInitialUpdate();
 }
diff --git a/modules/juce_gui_extra/native/javascript/index.js b/modules/juce_gui_extra/native/javascript/index.js
index 228e29314246..8104641401e4 100644
--- a/modules/juce_gui_extra/native/javascript/index.js
+++ b/modules/juce_gui_extra/native/javascript/index.js
@@ -152,7 +152,8 @@ class SliderState {
       label: "",
       numSteps: 100,
       interval: 0,
-      parameterIndex: -1,
+      parameterIndex: -1,
+      defaultValue: 0
     };
     this.valueChangedEvent = new ListenerList();
     this.propertiesChangedEvent = new ListenerList();