Other Test Sites


Zvon.org References

Zvon.org contains references for many XML‐related standards, including XHTML, MathML, XSLT, CSS, and SVG. The references contain functional examples, which could also be used as compliance tests.

Browser Standards Compliance QA maintained by Gerardo Kvaternik

The Mozilla standards compliance team has an exhaustive test suite for HTML, XHTML, XML, CSS, JavaScript, and DOM compliance. Not only does each attribute of each element have its own test page, sometimes there are separate pages for each value of each attribute.

Evil Test Suite by Ian Hickson

An outstanding HTML and CSS test suite, with a database of results in different browsers. Includes torture tests for fine points like collapsing empty paragraphs, underline color different from text color, and setting styles on <html> and <head> elements.

Pete’s Guide: Web Browser Tests by Peter Sheerin

Pete’s suite tests support for advanced HTML, XHTML, and XML markup, PNG images, integrated MathML and SVG, and useful Unicode typesetting, technical, and mathematical characters.

i‐Bench by PC Magazine

This downloadable automated performance test suite includes HTML 4.0, HTML 3.2, XML with CSS, and XML with XSL compliance tests, as well as tests for audio, video, and 3D file types.

Browser Buster by Chris Hoffman

Stress tests designed to push Mozilla’s endurance. Loads lists of pages for as long as the browser continues to run.

MauveCloud’s Browser Tests by Brian McCloud

Tests for character sets, HTML 2.0, 3.2, and 4.01, JavaScript 1.0–1.5, and image and sound file formats.

Character Sets

Alan Wood’s Unicode Resources by Alan Wood

Includes a suite of test pages covering the full range of Unicode 3.2 characters, and a information about Unicode support in fonts, Web browsers, and other software.

Browser Tests of Entities in 2004 by Nancy

Table of browser support for various character entities.

Image Formats

PngSuite by Willem van Schaik

Collection of graphic images designed to test support for the PNG standard.

Markup Languages


OBJECT test suite by Antti Näyhä

Test suite for the various features of HTML 4.0’s <object> element, using many different content types.

HTML 4.0 special characters by Dave Yost

Test for character entities.

iCab Browser‐Test by Alexander Clauss

Brief tests demonstrating iCab support of several HTML 4.0 features.

Dark Side of the HTML by Jno Cook

Since HTML is an application of SGML, HTML Web browsers technically should support SGML features like tag minimization (<em/example/). This officially dead site tests this and other features of SGML syntax.

XHTML Test Page

A simple page I made to test XHTML Basic served with various content types.


MathML Test Suite 2.0 by the World Wide Web Consortium (W3C)

The official MathML 2.0 test suite by the standards body itself.


Wireless FAQ Demos

Demonstrations and tests of various WML features.

Related Languages


RichInStyle.com tests by RichInStyle.com

Tests for every aspect of the CSS2 specification. RichInStyle.com also has detailed documentation of CSS bugs in major browsers.

Cascading Style Sheets Test Suites by the World Wide Web Consortium (W3C)

Official test suites by the CSS working group. The CSS level 1 test suite is comprehensive. There are also tests for Mobile Profile 1.0 and CSS level 3 selectors.

CSS2 Test Suite Prototype by Eric A. and Kathryn S. Meyer

Prototype of an official CSS level 2 test suite for the W3C.

CSS Tests by David Baron

Detailed tests covering much of CSS level 2.

Tests de conformité aux CSS 2 by Daniel Glazman

The Web site for his book, CSS 2: Feuilles de styles HTML, contains a CSS level 2 test suite, in French.

The Box Acid Test

A tough but fair composite test of the CSS‐1 box model as applied to HTML 4.0.


Document Object Model Conformance Tests

Downloadable set of 800 ECMAScript tests of DOM level 1 support, including the Fundamental, Extended and HTML features.

Web Development


Designing With Web Standards (2nd Edition) by Jeffrey Zeldman

A fine book preaching the advantages and teaching the techniques of forward‐compatible standards‐based Web design.


index DOT Html by Brian Wilson

Documentation of elements and attributes from HTML 2.0 through XHTML 1.1 (and proprietary ones too), with tables listing what versions of Internet Explorer, Mosaic, Netscape, and Opera support them.

HTML Help by The Web Design Group

I rely on their excellent online validation and link checking services, They have a useful and not overly technical HTML 4.0 reference, and articles on HTML style.


Documents about WWW written or recommended by Jukka Korpela

Yucca’s articles about Web authoring are recommended reading. The articles elsewhere on the Web that he recommends are also worthwhile.

Doctype switching and standards compliance by Matthias Gutfeldt

Review of browsers that choose between quirky and more standards‐compliant modes based on the <!DOCTYPE> declaration of a Web page, listing many other resources on the subject.

Subotnik: The 'link'‐Element in (X)HTML by Michael Nahrath

Extensive list of documents related to the use of the underused <link> element. In English and German.

OBJECT and Internet Explorer by Mark Pilgrim

Mark’s weblog Dive Into Mark posted an essay about <object>, which linked to my object test page with the annotation, This shows just how incredibly broken IE/Win’s OBJECT handling is. Over the next few days, other Web development blogs mentioned the story and also linked to my page. The cumulative effect was a surprising surge of hits to the object test page in particular and my test suite in general.