What is web accessibility auditing

A web accessibility audit measures your website's level of accessibility in a systematic way against a specific set of accessibility checkpoints as noted earlier. The internationally recognised benchmark for web accessibility is the Web Accessibility Initiative (WAI) Web Content Accessibility Guidelines (WCAG). To gain maximum benefit and value from an audit it should result in a list of actions to improve accessibility.

The individual components of this definition are:

  • measure – the audit should, as far as possible, deal in measurable quantities, not in estimates or opinion.  The vast majority of accessibility checks are measurable;
  • level of accessibility– accessibility is not a matter of yes or no. An audit will place your site somewhere on a curve between very low accessibility and excellent accessibility;
  • systematic – the measurement of accessibility has to be done in a planned and organised way;
  • accessibility checkpoints –  accepted checkpoints, usually international ones, are the basis on which the audit should be conducted;
  • actions – an audit must do more than highlight accessibility breaches. It must provide a roadmap for improvement.

An accessibility audit is also sometimes referred to as a conformance evaluation to determine if a website meets accessibility standards.

An accessibility audit can be used to facilitate the decision-making process around whether to attempt to fix the non-accessible elements of the website or to redesign the entire site.  This decision will also depend on the resources (financial and human) available.

A web accessibility audit typically results in a report that details:

  • the overall conformance rating of the website with WCAG;
  • a prioritised list of issues that need to be addressed;
  • details on the website's conformance with each of the accessibility checkpoints.

Carrying out a web accessibility audit also presents a good opportunity to increase capacity and technical skills within the organisation around accessibility.  It is a good time to enhance skills of in-house staff through specialised training and/or skills transfer from external consultants.

Accessibility guidelines

Web Content Accessibility Guidelines (WCAG) from the Web Accessibility Initiative (WAI)

The World Wide Web Consortium (W3C) is an international body that aims to lead the web to its full potential. It develops technologies, including specifications, guidelines, software and tools. The Web Accessibility Initiative (WAI) promotes accessibility by developing guidelines, support materials and resources.

The WAI published Web Content Accessibility Guidelines (WCAG) are regarded as the international standard for accessibility. First published (version 1.0) as a recommendation in 1999, they are very widely accepted not only by disability organisations and governments around the world but also by the European Union.

WCAG 1.0 consists of 14 guidelines. Each one is a general principle of accessible design.  For example, WCAG Guideline 1 states: "Provide equivalent alternatives to auditory and visual content."

Each of the WCAG guidelines gives rise to one or more checkpoints. A checkpoint is an explanation of how a guideline applies in practice. For example, Checkpoint 1.1, which arises from Guideline 1, begins: "Provide a text equivalent for every non-text element¦ This includes: images, graphical representations of text (including symbols), image map regions, animations."

Most guidelines have more than one checkpoint. The checkpoints are assigned to one of three priority levels depending on how vital they are for accessibility of content.

Priority 1: A web content developer must satisfy this checkpoint. It is a basic requirement for some groups to be able to use web documents.

Priority 2: A web content developer should satisfy this checkpoint. This will remove significant barriers to accessing web documents.

Priority 3: A Web content developer may address this checkpoint. Satisfying this checkpoint will improve access to web documents.

Most guidelines with more than one checkpoint have checkpoints at different priority levels. For example, Guideline 1 has 5 checkpoints; 4 are Priority 1 but the fifth is Priority 3.

GUIDELINEStates a broad accessibility principleGuideline 1: Provide equivalent alternatives to auditory and visual content.
CHECKPOINTExplains how a guideline applies in practiceCheckpoint 1.1 (extract): Provide a text equivalent for every non-text element. This includes: images, graphical representations of text (including symbols), image map regions, animations.
PRIORITYSets how important a checkpoint is to accessibility of contentCheckpoint 1.1 is Priority 1 – a basic requirement that must be satisfied
CONFORMANCE LEVELWhat checkpoints must be satisfiedWith all Priority 1 checkpoints satisfied, content is at conformance level A


The WCAG defines three levels of conformance. These may be claimed on a page-by-page basis, so different pages on a single website can have different claimed levels of conformance. Alternatively, a single conformance claim can refer to a defined collection of pages (a section of a website) or to a complete site.

Although the word "page" is used here, accessibility requirements apply to all resources on the website, including documents, interfaces, images, audio and video.

Many other guideline sets are based on WCAG. The WAI is due to complete work on a new version, WCAG 2.0, in 2007. The WAI says WCAG 2.0 will be much more robust, technology-independent, testable and with more supporting information than WCAG 1.0

Double-A conformity – satisfying all Priority 1 and 2 checkpoints is the minimum standard expected of public sector websites in Ireland. Many departments and agencies aim for Triple-A conformity, which requires conformance with a further 19 checkpoints.

NDA IT Accessibility Guidelines

The National Disability Authority IT Accessibility Guidelines cover a number of ITchannels including the web, public access terminals, telecoms, smart cards and application software.  The web component of these guidelines comprises of:

  • a set of guidelines and checkpoints based on WCAG 1.0 but easier to read and understand;
  • a range of best practice guidance for  web developers, designers and content creators;
  • an introduction to web accessibility for managers.   This provides high-level information on issues of legal obligations, business benefits and processes to improve the accessibility of your organisation's website;
  • an IT Procurement Toolkit that provides guidance to buyers of IT products and services to include meaningful, measurable and accurate criteria on accessibility in Request for Tenders.

Other bodies

The Equality Authority works towards the elimination of discrimination in employment, the provision of goods and services, education, property and other opportunities to which the public generally have access.  It does so on 9 distinct grounds, one of which is disability.

In addition to research, it oversees the implementation of anti-discrimination policy and law. Subject to certain criteria, it provides legal representation to those who believe that they have been discriminated against.

If you have queries about your obligations in relation to your website, the Equality Authority may be able to assist you.

You may also be able to get advice about accessibility related to specific disability from the advocacy and support group for people with that disability. For example, the National Council for the Blind of Ireland has a Centre for Inclusive Technology. The centre provides consultancy in inclusive design and offers independent verification of accessibility through auditing and user testing.