UKOLN AHDS How To Evaluate A Web Site's Accessibility Level


Many Web developers and administrators are conscious of the need to ensure that their Web sites reach as high a level of accessibility as possible. But how do you actually find out if a site has accessibility problems? Certainly, you cannot assume that if no complaints have been received through the site feedback facility (assuming you have one), there are no problems. Many people affected by accessibility problems will just give up and go somewhere else.

So you must be proactive in rooting out any problems as soon as possible. Fortunately there are a number of handy ways to help you get an idea of the level of accessibility of the site which do not require an in-depth understanding of Web design or accessibility issues. It may be impractical to test every page, but try to make sure you check the Home page plus as many high traffic pages as possible.

Get A Disabled Person To Look At The Site

If you have a disability, you have no doubt already discovered whether your site has accessibility problems which affect you. If you know someone with a disability which might prevent them accessing information in the site, then ask them to browse the site, and tell you of any problems. Particularly affected groups include visually impaired people (blind, colour blind, short or long sighted), dyslexic people and people with motor disabilities (who may not be able to use a mouse). If you are in Higher Education your local Access Centre [1] may be able to help.

View The Site Through A Text Browser

Get hold of a text browser such as Lynx [2] and use it to browse your site. Problems you might uncover include those caused by images with no, or misleading, alternative text, confusing navigation systems, reliance on scripting or poor use of frames.

Browse The Site Using A Speech Browser

You can get a free evaluation version of IBM's Homepage Reader [3] or pwWebSpeak [4], speech browsers used by many visually impaired users of the Web. The browsers "speak" the page to you, so shut your eyes and try to comprehend what you are hearing.

Alternatively, try asking a colleague to read you the Web page out loud. Without seeing the page, can you understand what you're hearing?

Look At The Site Under Different Conditions

As suggested by the World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI) [5], you should test your site under various conditions to see if there are any problems including (a) graphics not loaded (b) frames, scripts and style sheets turned off and (c) browsing without using a mouse. Also, try using bookmarklets or favelets to test your Web site under different conditions: further information on accessibility bookmarklets can be found at [6].

Check With Automatic Validation Tools

There are a number of Web-based tools which can provide valuable information on potential accessibility problems such as Rational Policy Tester Accessibility [7] and The Wave tools [8]. You should also check whether the underlying HTML of your site validates to accepted standards using the World Wide Web Consortium's MarkUp Validation Service [9] as non-standard HTML can also cause accessibility problems

Acting on Your Observations

Details of any problems found should be noted: the effect of the problem, which page was affected, plus why you think the problem was caused. You are unlikely to catch all accessibility problems in the site, but the tests described here will give you an indication of whether the site requires immediate attention to raise accessibility. Remember that improving accessibility for specific groups, such as visually impaired people, will often have usability benefits for all users.

Commission an Accessibility Audit

Since it is unlikely you will catch all accessibility problems and the learning curve is steep, it may be advisable to commission an expert accessibility audit. In this way, you can receive a comprehensive audit of the subject site, complete with detailed prioritised recommendations for upgrading the level of accessibility of the site. Groups which provide such audits include the Digital Media Access Group, based at the University of Dundee or the RNIB, who also audit Web sites for access to the blind.

Further Information

Additional information is provided at


This document was written by David Sloan, DMAG, University of Dundee and originally published at by the JISC TechDis service We are grateful for permission to republish this document.


  1. Access Centres,
  2. Lynx,
  3. Homepage Reader, IBM,
  4. pwWebSpeak,
  5. Web Content Accessibility Guidelines, Appendix A, W3C WAI,
  6. Bookmarklets: An aid to checking the accessibility of your website, Nicola McIlroy
  7. Rational Policy Tester Accessibility,
  8. WAVE,
  9. W3C HTML Validator, W3C,