.RNC file extension

This is the basic program to work with .RNC extension

Oxygen XML Editor

Oxygen XML Editor Relax NG Compact Syntax Schema

You can use Oxygen XML Editor in conjunction with all XML-based technologies and it includes a large variety of powerful tools for creating, editing, and publishing XML documents. The toolbars in Oxygen XML Editor can be customized according to your specific needs... (more)

The program works with the following extensions: xml, fo, xq, mod, nrl, rnc, xsl, rng, dtd, xsd, xpr, ent, sch, dita, nvdl, wsdl, xslt, xquery, ditamap and xevgenxml

.RNC extension is also supported by the following programs:

<oXygen/> XML Editor

XML Editor Relax NG Schema (Compact Syntax)

XML Copy Editor

XML Copy Editor MySQL Tools for

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