diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 2d934f8bc4466..e718e7987797b 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Added Numeric#in_milliseconds, like 1.hour.in_milliseconds, so we can feed them to JavaScript functions like getTime().
+
+	*DHH*
+
 *   Calling ActiveSupport::JSON.decode with unsupported options now raises an error.
 
     *Godfrey Chan*
diff --git a/activesupport/lib/active_support/core_ext/numeric/time.rb b/activesupport/lib/active_support/core_ext/numeric/time.rb
index 87b9a23aef488..d97ce938c1fad 100644
--- a/activesupport/lib/active_support/core_ext/numeric/time.rb
+++ b/activesupport/lib/active_support/core_ext/numeric/time.rb
@@ -76,4 +76,10 @@ def since(time = ::Time.current)
 
   # Reads best without arguments:  10.minutes.from_now
   alias :from_now :since
+
+  # Used with the standard time durations, like 1.hour.in_milliseconds -- 
+  # so we can feed them to JavaScript functions like getTime().
+  def in_milliseconds
+    self * 1000
+  end
 end
diff --git a/activesupport/test/core_ext/numeric_ext_test.rb b/activesupport/test/core_ext/numeric_ext_test.rb
index 1da72eb17d74c..23bbb8d7d2b09 100644
--- a/activesupport/test/core_ext/numeric_ext_test.rb
+++ b/activesupport/test/core_ext/numeric_ext_test.rb
@@ -440,4 +440,8 @@ def test_to_s__injected_on_proper_types
     assert_equal BigDecimal, BigDecimal("1000010").class
     assert_equal '1 Million', BigDecimal("1000010").to_s(:human)
   end
+  
+  def test_in_milliseconds
+    assert_equal 10_000, 10.seconds.in_milliseconds
+  end
 end