XML ValidatorBuddy!

XML Copy Editor is a fast, free, validating XML editor.

Altova XMLSpy is the industry's best-selling XML editor and development environment for modeling, editing, transforming, and debugging XML-related technologies. It offers the world’s leading graphical schema designer, a code generator, file converters, debuggers, profilers, full database integration, support for XSLT, XPath, XQuery, WSDL, SOAP, XBRL, and Office Open XML (OOXML) documents, plus Visual Studio and Eclipse plug-ins, and more.

<oXygen/> XML Editor is a cross platform XML Editor providing tools for XML authoring, XML conversion, XSL, XSLT, XQuery, XML Schema, DTD, Relax NG and Schematron development, SOAP and WSDL.

Firstobject's free XML editor for Windows is called foxe.

The simple yet actually fast source-level XML Editor XML Marker uses a combination of syntax-highlighting editor, tree view, and table views to help you get better insights of your XML code.

The Exchanger XML Editor is a Java-based product that provides unique functionality for viewing, authoring and editing XML data and documents. Last version was opensourced in 2010: https://code.google.com/archive/p/exchangerxml/downloads

Guide to learn programming

ExamXML displays XML documents in a tree view, highlighting differences down to the level of elements, words or attributes, so that you can view exactly which attributes and elements have been added, modified or deleted. Red color means that the element has been removed, green means that the element has been changed.

XMLFox XML/XSD editor is the Windows based graphical tool for authoring, updating, exploring, well-formedness checking or validating XML documents. XMLFox is a graphical XML editing and validation tool for creating valid, well-formed XML documents and/or XSD Schema. It includes an XML View, XML Tree, XML Grid, and XML Script modes for editing, as well as extensive find capabilities for text and XML data. Additional features include XML and Schema Validation, standard editing features, XSD Schema building and more. XMLFox is an intuitive xml and xml schema (XSD) editor, allows the xml developer to create schemas and show a visual representation of what the xml document will look like for that schema. »