Web Content Accessibility Guidelines: Understanding WCAG 2.0


WCAG (Web Content Accessibility Guidelines) 2.0, published in 2008, is a set of guidelines for creating accessible digital content for people with disabilities. WCAG 2.1, published in 2018, extends WCAG 2.0 by adding new requirements.
Originally Published: 09/21/2015
Understanding Web Content Accessibility Guidelines 2.0
- Under the World Wide Web Consortium (W3C), the Web Accessibility Initiative (WAI) developed the Web Content Accessibility Guidelines (WCAG) 2.0 to produce standards and guidelines to make the web accessible for people with disabilities.
- WCAG 2.0 focuses on website content and structure.
- As a technical standard, WCAG 2.0 primarily establishes guidelines, mainly used by web content developers and tool developers to make websites accessible for people with disabilities.
The Web Content Accessibility Guidelines are digital accessibility guidelines published by the World Wide Web Consortium (W3C), the primary international standards organization for the World Wide Web. These guidelines assist developers in making content accessible — not only for individuals with disabilities, but for all users.
Currently, the W3C recommends following WCAG 2.1, with WCAG 2.2 scheduled to become an official recommendation in the near future. We’ll explain the differences between WCAG versions later in this article.
However, WCAG 2.0 remains important for digital compliance. Many non-discrimination laws, such as Section 508 of the Rehabilitation Act of 1973, incorporate WCAG 2.0 by reference.
The goals of WCAG are to:
- Connect the world through common information technology and user experience standards.
- Provide best practices for multiple types of devices and software.
- Continually evolve and adapt through frequent review and community support.
WCAG 2.0 vs. 2.1: What’s the Difference?
As technologies change, the W3C occasionally updates WCAG to introduce new requirements. Each version of WCAG is intended to expand on previous versions — not to replace them.
WCAG 2.0 was introduced in back in December 2008, and the internet has certainly changed significantly since then. In 2018, WCAG 2.1 became an official recommendation.
Here are a few key differences between WCAG 2.0 and 2.1:
- WCAG 2.1 introduced 17 new requirements (or success criteria).
- Many of those new requirements focus on making content accessible for smartphones and other mobile devices.
- Many international digital accessibility laws cite WCAG 2.0. However, the European Accessibility Act and other recent laws have required WCAG 2.1 conformance.
WCAG 2.2 is expected to include 9 new success criteria. However, it’s currently a working draft, not an official recommendation — read more about WCAG 2.2.
Who Needs to Conform to WCAG 2.0?
Every organization has an ethical responsibility to provide the best possible experience to people with disabilities. In most countries, businesses also have a legal responsibility.
WCAG 2.0 conformance is explicitly required for U.S. government agencies (and in most cases, their contractors). And while Title III of the Americans with Disabilities Act (ADA) does not include technical requirements for websites and other digital content, the Department of Justice (DOJ) recommends using WCAG to test for compliance.
It’s also important to note that many non-discrimination laws apply to all digital communications — that includes websites, but also mobile apps, web-delivered documents (such as PDFs), and emails.
If you’re building a digital accessibility strategy, the best practice is to use the latest official recommendations from the W3C. Currently, that means testing your content against WCAG 2.1’s Level A/AA success criteria (we’ll discuss WCAG’s conformance levels shortly).
But if your content conforms with any version of WCAG 2.X, you’re in a good position for compliance: Each version contains all of the success criteria from previous versions.
Getting to Know WCAG 2.0 Guidelines

The purpose of WCAG is to improve experiences for people with all types of abilities. That includes individuals with conditions that affect their hearing, vision, mobility, cognition, and memory.
To that end, WCAG is based on four principles of accessibility. Each principle is divided into guidelines, which are basic rules for building better content.
The guidelines can be tested with success criteria, which are simple pass-or-fail statements. Techniques are the W3C’s recommendations for fulfilling the success criteria.
Below, we’ll provide a basic overview of this hierarchy, then explain how to use WCAG to test your content.
WCAG 2.0 Hierarchy
- Principles: 4
Guidelines: 12
Testable Success Criteria: 61
Priority Conformance Levels: A (25), AA (13), AAA (23)
Techniques: 450+ (and growing)
For detailed criteria and a complete accessibility matrix, please visit the links provided in the sources list below.

Principles & Guidelines
To understand WCAG, you’ll need to remember that accessibility is a mindset, not a checklist. The four principles of accessibility can help you apply the guidelines more effectively — and build content that works for a much wider audience.
1. Perceivable
Information and user interface components must be presentable to users in ways they can perceive.
1.1. 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.
1.2. Provide alternatives for time-based media.
1.3. Create content that can be presented in different ways (for example simpler layout) without losing information or structure.
1.4. Make it easier for users to see and hear content including separating foreground from background.
2. Operable
User interface components and navigation must be operable.
2.1. Make all functionality available from a keyboard.
2.2. Provide users enough time to read and use the content.
2.3. Do not design content in a way that is known to cause seizures.
2.4. Provide ways to help users navigate, find content, and determine where they are.
3. Understandable
Information and the operation of user interface must be understandable.
3.1. Make text content readable and understandable.
3.2. Make Web pages appear and operate in predictable ways.
3.3. Help users avoid and correct mistakes.
4. Robust
Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.
4.1. Maximize compatibility with current and future user agents, including assistive technologies.
Techniques are technology-specific (General, HTML, CSS, ARIA, etc.)
Types include:
- Sufficient – minimum requirements
- Advisory – additional improvements
- Failure – often encountered mistakes
Contents include:
- Applicability
- Description
- Examples
- Resources
- Related Techniques
- Tests (Procedures)

The Five WCAG Conformance Requirements
As we’ve discussed, WCAG is organized by three levels of conformance (conformance means voluntarily following the requirements, as opposed to compliance, which is mandatory).
To earn conformance, you’ll need to set a goal — most organizations should try to meet all Level A and Level AA success criteria.
Number 1: WCAG Levels
Level A is considered the minimum degree of accessibility and covers basic web accessibility. Level AA is considered the mid-range degree of accessibility and covers the most common barriers people with disabilities encounter on the web. The highest degree is Level AAA and is the uppermost level that can be reached for website accessibility.
The standard conformance degree is Level AA.
If you have conformance at a higher level, you will have conformance at the lower levels. For example, if you comply with Level AAA, you also comply with Level AA and A and if you comply with Level AA, you also comply with Level A.
Number 2: Full Pages
Full pages must conform to the conformance level. Parts of pages must not be excluded to meet conformance.
Number 3: The Complete Process
If more than one page is part of a process that is needed to complete a product or activity, they must all meet the conformance level to the same degree. The only way that it is accessible, is if the web page meets the same or higher conformance level than the rest.
Number 4 & 5: Usability of Accessibility Supported Technologies
If more than one page is part of a process that is needed to complete a product or activity, they must all meet the conformance level to the same degree. The only way that it is accessible is if the web page meets the same or higher conformance level than the rest.
In short, web pages must be accessible to people using assistive technologies and user agents. If the web page uses technology that is not accessibility supported, it must not block or create barriers for technology that is accessibility supported.

How to Improve Web Accessibility and Conform to WCAG 2.0
To conform with any version of WCAG, you’ll need to audit your website regularly — particularly if you regularly add new content, or if your content changes dynamically.
You’ll also need to incorporate the best practices of accessibility into your website’s development. That means reviewing the guidelines and ensuring that your entire team understands the importance of digital compliance.
AudioEye provides a downloadable Comprehensive Guide on Accessible Web Design to help designers learn essential concepts of accessibility.
To test content against WCAG 2.0 or 2.1, the best approach is to use a combination of manual and automated tests:
- Manual tests are performed by a human — usually a person who has experience with screen readers and other assistive technologies. Manual tests are accurate, but they can be time consuming, especially on larger websites.
- Automated tests check your content against the WCAG criteria that have simple pass-or-fail rules. Automated testing is helpful for finding issues like low-contrast text, poor keyboard accessibility, and missing image alternative text.
AudioEye provides a free Website Accessibility Checker, which performs more than 400 tests against the latest version of WCAG. For additional guidance, read: How to Choose a Web Accessibility Tool.
Fixing WCAG 2.0 Conformance Errors
In some cases, “fixing" an accessibility issue may make the problem worse — to ensure digital compliance, you should always follow WCAG’s recommended techniques.
AudioEye’s accessibility platform is designed to help businesses meet their digital compliance goals by combining powerful automation with guidance from accessibility experts. Our solution tests content every time the page loads, fixing many issues automatically.
But while artificial intelligence has come a long way, some accessibility issues require human judgment. AudioEye also provides guidance for manual fixes and access to a 24/7 help desk, along with manual remediation services performed by experienced accessibility experts.
Is WCAG 2.0 a Legal Requirement?
WCAG 2.0 is a legal requirement for federal agencies under the Revised Section 508 standards of the Rehabilitation Act of 1973. Private businesses also have a legal responsibility under Title III of the ADA, but the ADA does not include specific technical requirements for digital compliance.
However, in July 2023, the DOJ advanced a proposed rule to strengthen web and mobile app accessibility by establishing WCAG 2.1 Level AA as a requirement for ADA Title II compliance.
And while the ADA currently lacks technical standards, digital accessibility is still enforceable. The U.S. Department of Justice has reached settlements with places of public accommodation to have their websites use the guidelines set forth in WCAG 2.0 to become compliant with the Americans with Disabilities Act.
The bottom line: Even if WCAG compliance is not explicitly necessary, businesses can reduce their legal risks by following the Level A/AA requirements of the current version of WCAG. Currently, the DOJ recommends testing content against WCAG 2.1.

WCAG 2.0: An Internationally Accepted Standard
Many countries, provinces, and states have introduced website accessibility laws that reference WCAG 2.0 or 2.1.
WCAG has been embraced as the international standard and has been directly referenced or adopted by at least 14 countries and the European Union. Some examples:
- Australia’s Disability Discrimination Act of 1992.
- Ireland’s Equal Status Acts 2000 to 2004 and the Equal Rights of Persons with Disabilities Act.
- United Kingdom’s Equality Act of 2010.
- Ontario, Canada’s Accessibility for Ontarians with Disabilities Act (AODA).
- The E.U.’s European Accessibility Act (EAA) and European Web Directive.
While penalties for noncompliance vary, most countries allow people with disabilities to file lawsuits against non-compliant businesses.
In the United States, digital accessibility lawsuits filed under the ADA have increased significantly over the last decade — and since most websites fail to meet WCAG’s basic requirements, that trend will likely continue.
Create a More Accessible Website Today with AudioEye
By embracing WCAG, you can enjoy the substantial benefits of accessibility. WCAG conformance can improve search engine optimization (SEO) and increase traffic. Publishing an accessible website certification can improve your brand by showing customers that you care about their experiences.
AudioEye can help you get started. We believe that our solution provides the best path to digital compliance, with options designed to meet the needs of businesses of all sizes.
To start building for accessibility, test your website with our Website Accessibility Checker or schedule a demo.
Source Materials
World Wide Web Consortium
Introduction to WCAG
Understanding Conformance
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