# CKEditor Samples » Producing XHTML Compliant Output

This sample shows how to configure CKEditor to output valid XHTML 1.1 code. Deprecated elements (`<font>`, `<u>`) or attributes (`size`, `face`) will be replaced with XHTML compliant code.

To add a CKEditor instance outputting valid XHTML code, load the editor using a standard JavaScript call and define CKEditor features to use the XHTML compliant elements and styles.

A snippet of the configuration code can be seen below; check the source of this page for full definition:

    CKEDITOR.replace( 'textarea_id', {
    	contentsCss: 'assets/outputxhtml.css',

    	coreStyles_bold: {
    		element: 'span',
    		attributes: { 'class': 'Bold' }
    	},
    	coreStyles_italic: {
    		element: 'span',
    		attributes: { 'class': 'Italic' }
    	},

    	...
    });

Editor 1: <p>This is some <span class="Bold">sample text</span>. You are using <a href="https://ckeditor.com/">CKEditor</a>.</p>