What are the Web Content Accessibility Guidelines (WCAG)?

The Web Content Accessibility Guidelines, often simply referred to as WCAG, are website accessibility guidelines created and published by the World Wide Web Consortium (W3C). They represent the internationally recognised standard for web content accessibility.

The W3C is an international public-interest non-profit organisation founded by inventor of the World Wide Web Tim Berners-Lee. The WCAG web standards were and are developed with W3C member organisations, staff and the public working collaboratively.

The Web Accessibility Initiative (WAI), part of the W3C, maintains the WCAG web standards and produces support materials to help everyone understand and implement accessibility best practices across websites and other digital services.

AbilityNet's relationship to WCAG is we are a global leader in digital accessibility and a Founding Member of the International Association of Accessibility Professionals (IAAP). We have one of the biggest teams of specialist consultants in the UK and help organisations of all types and sizes to become more inclusive and to build accessible digital products and services that are compliant with the WCAG web standard. Contact us if you are interested in making accessibility a priority at your organisation.

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For a more general overview of web and digital accessibility visit our ‘What is digital accessibility?’ page or continue reading for more information specifically about WCAG, including answers to the following questions:

• What are the 4 principles of WCAG?
• What is the latest version of WCAG?
• How many WCAG guidelines and success criteria are there?
• How do I check my website WCAG compliance?
• How do I make my website WCAG compliant?
• Are WCAG guidelines law?

What are the 4 principles of WCAG?

In the structure of the WCAG there are 4 principles of web content that provide the foundation for web accessibility, and these are that it should be perceivable, operable, understandable and robust.

1. Perceivable: users must be able to perceive the information and interactive elements being presented to them. They should be able to observe and engage with content through their senses. As an example, a blind person using a screen reader should hear a description of a non-decorative image. 
2. Operable: user interfaces and interactive components must be operable. As an example, a keyboard-only user should be able to complete all actions and navigation on a website using only their keyboard. 
3. Understandable: users must be able to understand the information as well as the operation of a user interface. It cannot be beyond their understanding. As an example, the expanded form of an abbreviation should be made available the first time it appears within a web page e.g. Web Accessibility Initiative (WAI). 
4. Robust: content must be robust enough to be interpreted reliably by a wide variety of users and devices, including assistive technologies, with content remaining accessible as technology advances. As an example, a link on a web page should be correctly marked up as a link using standard HTML (HyperText Markup Language). 

For more information about the 4 principles of WCAG visit the W3C website. 

What is the latest version of WCAG?

Version 1.0 of WCAG launched on 6 May 1999. WCAG 2.0 was published on 11 December 2008 with a specific focus on screen reader compatibility and making web content accessible to people with visual impairments.

WCAG 2.1 or 2.2?

WCAG version 2.1 became a W3C recommendation in June 2018, with WCAG version 2.2 published October 2023 having a focus on neurodiversity including the needs of people with Autism, Dyspraxia, Dyslexia, Dyscalculia, Dysgraphia and Tourette syndrome. 

WCAG version 2.2 is the current W3C recommendation (correct as of October 2023 when it was published). For more information read our free factsheet on what you need to know about WCAG 2.2.

When will WCAG 3.0 be released?

Looking further ahead to WCAG 3.0, this will expand to address a broader range of user needs, is expected to have a more comprehensive approach to mobile accessibility and a new emphasis on emerging technologies such as augmented and virtual reality. 

Many aspects of WCAG 3.0 are in an exploratory phase and will change. An updated working draft was published on 16 May 2024 but WCAG 3.0 is not expected to be a completed W3C standard for a few more years. For more information you may be interested in our free resource on ‘What to expect from the WCAG 3.0’.

How many WCAG guidelines and success criteria are there?

WCAG version 2.2, which is the current W3C recommendation (correct as of October 2023 when it was published), has a total of 13 guidelines. In the structure of WCAG standards guidelines sit under principles and provide the overall basic goals users should work toward in order to make web content more accessible to all users. 

As an example, Guideline 1.1 Text Alternatives directs users to ‘Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language’. 

For each guideline there are testable success criteria and WCAG 2.2 contains 86 success criteria. In order to meet the needs of different groups and different situations, three levels of conformance are defined by WCAG: level A (lowest), level AA, and level AAA (highest). 

As an example, the success criterion for Guideline 1.1 directs that at level A ‘All non-text content that is presented to the user has a text alternative that serves the equivalent purpose [except for specific situations]’. 

You can find more information about levels of WCAG conformance on the W3C website.

How do I check my website WCAG compliance?

To evaluate web content and to tell if a website is WCAG compliant there will often be the need for a review. Due to the specialist nature of the checks required, the value of independent assessment, and the technical detail of the WCAG and their success criterion, many organisations will choose to work with external consultants. 

Our team of qualified experts conduct WCAG checks and accessibility audits to the highest standards. We offer a range of web accessibility audit and testing services, from our Headline Review which identifies priority issues from a sample of web pages to a Full Audit where we will comprehensively review your website. 

We also specialise in disabled user research and user testing, gathering feedback from a diverse range of users on a digital product or service, including disabled and older people. By actively involving diverse users in our review and testing processes, we can help you ensure that your products are truly inclusive and accessible to all.

Alternatively, if you would like to be able to check your own web accessibility you can gain relevant skills via training courses such as our Accessibility testing training on topics including How to begin your own accessibility testing training and How to do inclusive usability testing. 

Download our services brochure for information about the services we offer, including training, or contact us for support checking the accessibility of your web content.

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How do I make my website WCAG compliant?

The W3C WCAG standards and drafts are readily available on the W3C website, as are supporting documents on topics including how to meet WCAG 2.2, understanding WCAG 2.2 and techniques for WCAG 2.2. These can be used by anyone developing web content.  

However, if you are not familiar with WCAG it can be difficult to approach the guidelines in a meaningful way in your day-to-day work. Our accessibility and inclusive design training offers a pathway to gaining understanding and practical accessibility skills.  

We offer courses specific to roles including content creators, designers, developers, project managers and testers. We understand each person will be at a different stage in their accessibility journey and our training offering reflects this. 

Equally, you may not have the resources to ensure you are meeting WCAG standards correctly and consistently. In this case, partnering with an organisation like AbilityNet may be advantageous. We are a global leader in web and digital accessibility, based in the UK, with one of the biggest teams of specialist consultants. 

Download our services brochure for information about our services or contact us about your requirements and we will advise on a bespoke digital accessibility strategy. 

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Are WCAG guidelines law?

Whilst the WCAG standards themselves do not function as law, they represent the internationally recognised standard for web content accessibility, and you will meet the legal requirements for accessibility by meeting the WCAG standard.

Who is required to comply with WCAG?

Ensuring your website is accessible is covered by the Equality Act 2010 in the UK, which protects all individuals from unfair treatment and promotes a fair and more equal society. 

There are equivalent laws in other countries, which encompass web accessibility law and legislation, such as the Americans with Disabilities Act (ADA) of 1990. The European Accessibility Act (EAA) seeks to ensure equal access to digital products and services throughout Europe and becomes law in all EU member states in June 2025. 

The Public Sector Bodies (Website and Mobile Applications) Accessibility Regulations (PSBAR 2018) apply to the UK public sector specifically and require public sector organisations to meet WCAG 2.2 guidelines at AA level of conformance, which from October 2024 will be monitored by the Government Digital Service (GDS).

What happens if your website is not accessible? 

Not ignoring the threat of legal action, it’s very important to consider the barriers you might be creating for people if you are not ensuring your web content is accessible. 

There are an estimated 16 million disabled people in the UK, and in 2019 the ‘Click-Away Pound’, which measures the volume of people who abandon a retail website because of the barriers they found, grew to £17.1 billion. 

Good accessibility practices benefit everyone, not just disabled people. Consider a person using captions when watching a video on a noisy train, or a worker with a sprained wrist using speech-to-text to write an email. Many of us use accessibility features every day. 

Our free guide to the Business Case for Accessibility will help you win hearts and minds inside and outside your organisation. 

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To find out more about WCAG and digital accessibility join our mailing list or take a look at our free digital accessibility resources. If you're ready to create meaningful change and achieve significant results, speak to our experts to learn how we can help you to achieve your accessibility goals.