diff --git a/dom/html/HTMLInputElement.h b/dom/html/HTMLInputElement.h
index fde12b817d..2321b7338e 100644
--- a/dom/html/HTMLInputElement.h
+++ b/dom/html/HTMLInputElement.h
@@ -796,6 +796,13 @@ public:
   void UpdateDateTimePicker(const DateTimeValue& aValue);
   void CloseDateTimePicker();
 
+  /*
+   * The following are called from datetime input box binding to get the
+   * corresponding computed values.
+   */
+  double GetMinimumAsDouble() { return GetMinimum().toDouble(); }
+  double GetMaximumAsDouble() { return GetMaximum().toDouble(); }
+
   HTMLInputElement* GetOwnerNumberControl();
   HTMLInputElement* GetOwnerDateTimeControl();
 
diff --git a/dom/webidl/HTMLInputElement.webidl b/dom/webidl/HTMLInputElement.webidl
index b2546fccac..c551d96ab6 100644
--- a/dom/webidl/HTMLInputElement.webidl
+++ b/dom/webidl/HTMLInputElement.webidl
@@ -253,6 +253,14 @@ partial interface HTMLInputElement {
   [Pref="dom.forms.datetime", ChromeOnly]
   void setDateTimePickerState(boolean open);
 
+  [Pref="dom.forms.datetime", ChromeOnly,
+   BinaryName="getMinimumAsDouble"]
+  double getMinimum();
+
+  [Pref="dom.forms.datetime", ChromeOnly,
+   BinaryName="getMaximumAsDouble"]
+  double getMaximum();
+
   [Pref="dom.forms.datetime", Func="IsChromeOrXBL"]
   void openDateTimePicker(optional DateTimeValue initialValue);