This online tool helps you to query XML/HTML documents with your browser in real-time and can generate queries for you.
Use your XPath query in the top-left panel and it will be instantly executed against this document. Once some results are displayed on the right, you can scroll to them by clicking on them.
To generate an XPath query for a specific element, please hold CTRL and hover over it.
This online tool is in an early beta version so please be forgiving.
The XPath 2.0 is supported but namespaces are still being added and they may not fully work yet.
You can use it on this webpage.