This converts CSS 3 Selectors to an XPath 1.0 expression. Some CSS 3 Selectors (especially pseudo-selectors) cannot be translated (you'll get an error if you try one of these). To access this programmatically GET http://css2xpath.appspot.com?css={css} -- the response will be the XPath expression (Content-Type: text/plain), or if there is an error the response code will be 400 Bad Request and the