Info

How much faster is the HTML5 document.head DOM tree accessor compared to its old-school variant, document.getElementsByTagName('head')[0]?

Preparation code

<script>
  document.head = document.head || document.getElementsByTagName('head')[0];
  
  Object.defineProperty(Document.prototype, 'head2', {
   get: function() {
    return this.head || this.getElementsByTagName('head')[0]
   }
  });
</script>

Test runner

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document.getElementsByTagName('head')[0];

document.head;

document.head2;

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published by Mathias Bynens on 31st July 2010 and last updated on 28th June 2011
• Revision 2: published by Charles Lehner on 3rd August 2010
• Revision 3: published by kangax on 11th August 2010 and last updated on 24th January 2011
• Revision 4: published by stefaan on 28th February 2011
• Revision 5: published on 27th October 2011
• Revision 6: published on 30th October 2011
• Revision 7: published by Ryun shofner on 18th February 2013

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