Where XML skills are forged. Two free interactive courses, a growing set of hand-built challenges, a daily puzzle, and a serious browser-based sandbox for XPath 1.0, XPath 3.1, and XQuery 3.1. Everything runs in your browser — the documents you query never leave your machine.
A three-pane workbench: your XML on one side, the query in the middle, results on the other. Matched nodes are highlighted in the document itself. Switch between XPath and XQuery, choose XPath 1.0 or 3.1, declare namespaces, pick a node to generate its path, and step through an expression one location step at a time.
Start with XML Foundations if XML itself is new — 14 lessons covering elements, attributes, well-formedness, escaping, CDATA, the prolog, namespaces, and the DOM. Then take the XPath course: 19 phases and roughly 107 lessons, from your first descendant path through XPath 3.1.
Challenges are hand-authored and tagged by technique and difficulty; each one asks for several distinct valid solutions rather than a single answer, so you learn the alternatives instead of the first thing that works. The Daily puzzle is one shared problem a day, with a streak and a global leaderboard.
A scannable reference for both languages: every axis, node test, predicate, and function for XPath, plus FLWOR, constructors, the prolog, and typeswitch for XQuery. Examples open in the Sandbox and run against real XML.
XPath reference · XQuery reference · XPath cheat sheet · FAQ