Glossary:WCAG (Web Content Accessibility Guidelines)
9 min.
What are the WCAG?
The WCAG (Web Content Accessibility Guidelines) are the international standard for accessible web content, developed by the World Wide Web Consortium (W3C). They define how websites, web apps, and digital content must be designed to ensure that people with disabilities can fully utilize them — regardless of whether they use a screen reader, a braille display, keyboard navigation, or other assistive technology.
The current version is WCAG 2.2 (released October 2023). WCAG 3.0 is still in development.
What many companies underestimate: 94.8% of the top 1 million websites worldwide have measurable WCAG errors — an average of 51 errors per page. German .de domains are slightly better with 47.8 errors per page but still far from WCAG compliance (Source: WebAIM Million Report, February 2025). Accessibility is not a niche topic — it is a widespread gap.
Why have WCAG been mandatory since June 28, 2025?
With the Barrier-Free Enhancement Act (BFSG), Germany has transposed the EU directive European Accessibility Act (EAA) into national law. Since June 28, 2025, B2C companies with more than 10 employees AND an annual turnover of more than 2 million euros must make their digital products and services accessible.
In concrete terms, this means: Websites, apps, online shops, and digital interaction points must be WCAG-compliant — or companies risk fines of up to 100,000 euros in Germany (Source: §37 BFSG).
Affected are primarily:
Online retailers with their own webshop
Banks and insurance companies with digital customer access
Telecommunications providers
Booking and travel platforms
Public authorities (already obliged since 2018 by the BITV 2.0)
Those using branchly need not worry about the AI layer: branchly is WCAG-accessible out of the box. All modules — chatbot, AI search, navigator, advisor, and forms — meet WCAG requirements without additional configuration effort.
The four WCAG Principles: POUR
The WCAG is based on four fundamental principles, known by the acronym POUR:
1. Perceivable
All content must be presented in a way that users can perceive it — even if they have a visual or auditory impairment. This includes text alternatives for images, captions for videos, and sufficient color contrasts.
2. Operable
All navigation and interaction must work without a mouse. Users who only use a keyboard or other input device must be able to access all functions.
3. Understandable
Content and interface elements must be clear and predictable. Error messages in forms must help understand and fix the error — not just indicate that an error has occurred.
4. Robust
Content must work with a variety of user agents and assistive technologies — including future technologies. This requires clean, semantic HTML code.
WCAG Compliance Levels: A, AA, AAA
Level | Description | Typical Requirement |
|---|---|---|
A | Minimum standard | Must be met — otherwise, use is impossible for certain groups |
AA | Recommended standard | Legal requirement in Germany (BFSG, BITV) and EU |
AAA | Highest level | For specialized offerings; not fully accessible for general websites |
Experience shows: For BFSG compliance, AA is sufficient. This is also the level referred to by European harmonization standards (EN 301 549).
Who benefits from WCAG-compliant websites?
Accessibility affects more people than many marketing teams assume.
In Germany, 7.9 million people have a severe disability — which corresponds to 9.3% of the population (Source: Destatis, July 2024). Across the EU, 23.9% of the population aged 16 and above have a disability — around 96 million people (Source: Eurostat, 2024).
Additionally, there are temporary impairments (broken arm, bright sunlight on the display) and situational barriers (noisy environment, poor Wi-Fi). Accessibility ultimately benefits all users — a principle that the W3C describes as the "curb cut effect."
What non-accessible websites cost: According to the British Click-Away Pound Study (2019), 69% of users with disabilities leave a non-accessible website — resulting in a loss of £17.1 billion in revenue in the UK (Source: Click-Away Pound, 2019). This is not a fringe issue, but a measurable economic damage.
Companies that consistently implement accessibility see it reflected in their numbers: Disability-inclusive companies achieve, on average, 1.6 times more revenue and 2.6 times more net profit than the industry average (Source: Accenture / Disability:IN, 2023).
WCAG-compliant website vs. non-accessible website
Criterion | WCAG-compliant website | Non-accessible website |
|---|---|---|
Legal Compliance | BFSG/EAA compliant since June 28, 2025 | Risk of fine up to €100,000 |
Reachable Target Audience | 100% of users including 96 million EU citizens with disabilities | Excludes up to 23.9% of the EU population |
Search Engine Optimization | Semantic HTML improves crawlability and Core Web Vitals | Missing alt texts and poor structure weaken SEO |
Bounce Rate | Low — users with assistive technologies stay | High — 69% of users with disabilities leave the page |
Form Experience | Clear error messages, keyboard navigation, ARIA labels | Forms often not usable for screen reader users |
Mobile Usability | Accessible controls work better on touch devices | Control issues increase on small displays |
Brand Perception | Signal for quality, trust, and social responsibility | Reputational risk from public criticism or warnings |
Technical Debt | Low due to a clean semantic codebase | High due to retrofitting accessibility afterward |
branchly customers receive the AI layer already WCAG-compliant. This means: Chatbot, AI search, and navigator do not add new barriers to the existing website — instead, they can actively close existing gaps in user guidance.
WCAG in practice: Common errors and how to fix them
The WebAIM Million Report (2025) lists the six most common WCAG errors on German and international websites:
Missing alt texts on images (54.5% of all reviewed pages affected)
Insufficient color contrasts between text and background (80.9%)
Missing form labels — input fields without descriptive text for screen readers
Empty links — links with no or non-descriptive text ("click here")
Missing document title in the
<title>tagMissing language designation in the HTML tag (
lang="de")
Many of these errors do not arise from negligence but because teams do not use an accessibility checklist during development. Tools like the WAVE browser extension or axe DevTools help to systematically identify these errors.
The Accessible Rich Internet Applications (ARIA) standard augments HTML where native semantics are insufficient — for instance, with dynamic content, modals, or custom UI components. branchly widgets are equipped with complete ARIA attributes and do not interfere with existing ARIA structures.
WCAG in practice: Use cases
E-Commerce
An online shop with a branchly chatbot and AI search already meets WCAG requirements at the level of interactive elements. Users with screen readers can navigate through product recommendations using the keyboard, ARIA labels identify form fields correctly, and contrasts meet the AA level. The result: The accessible AI layer is not an additional project but included by default. Over 40 million AI-driven sessions on branchly platforms demonstrate just how broad this user base really is (Source: branchly, 2026).
Tourism
Travel platforms and destination marketing organizations are among the companies obliged by the BFSG. A tourism portal using the branchly navigator guides users barrier-free through multi-step booking processes — with keyboard support, full screen reader compatibility, and multilingual output in all 101 natively supported languages. This is particularly relevant when international guests with different language settings come to the platform.
Public Administration
Authorities and public institutions have been required to provide accessibility since 2018 due to the BITV 2.0. The branchly navigator helps citizens navigate complex administrative processes step by step — via keyboard, screen reader, or in the user's language. The interaction rate for firmly embedded interfaces is between 45 and 50% (Source: branchly customer data, 2026) — a clear signal that users actively embrace guided navigation.
branchly and WCAG: The AI layer that builds no barriers
branchly has been developed from the outset with WCAG compliance as a design principle — not as an afterthought compliance project. This means for you:
Chatbot: Complete keyboard navigation, ARIA live regions for dynamic responses, sufficient contrast ratios
AI Search: Semantic search result lists, focus management, screen-reader-compatible autocompletion
Navigator: Step-by-step guidance with clear progress indicators and accessible form elements
Advisor: Product recommendations with descriptive alt texts and full keyboard control
Forms: ARIA labels, error identification according to WCAG 3.3, automatic focus on error messages
Over 11 million users have already been served through branchly modules (Source: branchly). The WCAG compliance is not a marketing promise but a technical reality — verifiable with WAVE, axe, and manual screen reader tests.
The entry point starts at €499/month (Starter, 1,000 sessions). With that, you get a WCAG-compliant AI layer that is ready to use immediately — without a separate accessibility audit for the AI layer.
Widget interaction rates of 5–10% (compared to 0.5–1% industry average) show: Accessibility does not equal less appealing. On the contrary — clear structures, good keyboard control, and understandable language benefit all users.
Related Terms
GDPR-compliant AI
EU AI Act
AI Chatbot
Conversational AI
AI Search
Guided Navigation
Frequently Asked Questions
What are the WCAG in simple terms?
The WCAG (Web Content Accessibility Guidelines) are international guidelines from the W3C that outline how websites must be designed so that people with disabilities can fully utilize them. They cover visual, auditory, motor, and cognitive impairments and are divided into three levels of conformance (A, AA, AAA). In Germany, WCAG 2.1 Level AA has been legally binding for affected B2C companies since June 28, 2025, according to the BFSG.
Who is affected by the BFSG?
The Accessibility Enhancement Act applies to B2C companies with more than 10 employees AND more than 2 million euros in annual revenue. It affects digital products and services that are launched or fundamentally revised after June 28, 2025. Public administrations have been subject to BITV 2.0 since 2018. Violations can result in fines of up to 100,000 euros (Source: §37 BFSG).
What is the difference between WCAG 2.1 and WCAG 2.2?
WCAG 2.2 (October 2023) extends the 2.1 version with nine new success criteria, primarily in the areas of keyboard navigation, focus indicators, and authentication. Level AA in 2.2 also removes an older criterion (4.1.1 Parsing) that was technically outdated. Currently, WCAG 2.1 AA is referenced for BFSG conformity in Germany, but an upgrade to 2.2 is advisable.
Why do so many websites fail to meet the WCAG?
According to the WebAIM Million Report (February 2025), 94.8% of the most visited websites have WCAG errors. The most common causes: missing alt texts, insufficient color contrasts, missing form labels, and empty links. Most errors are not intentional but occur because accessibility is not systematically integrated into development and design workflows.
How do I check if my website is WCAG compliant?
Automated tools like WAVE (webaim.org/wave), axe DevTools (browser extension), or Google Lighthouse uncover about 30–40% of errors. The rest can only be found through manual checking: testing keyboard navigation, using a screen reader (NVDA, VoiceOver, TalkBack), and measuring contrasts with the WebAIM Contrast Checker. For a complete evaluation according to BITV/BFSG, a certified accessibility audit is recommended.
What does retrofitting accessibility cost?
Much more than incorporating it from the start. Studies show that retroactive corrections are 30–100 times more expensive than if accessibility is considered in the development process. Retrofitting a large website can cost five to six-figure amounts. Ongoing maintenance costs for new content are also an additional consideration. With branchly, this effort for the AI layer is completely eliminated — accessibility is included by default.
Does WCAG compliance improve SEO?
Yes, indirectly. Many WCAG requirements overlap with SEO best practices: alt texts help crawlers, heading hierarchies improve content structure, semantic HTML facilitates indexing, and fast loading times benefit both screen reader users and Google ranking. Accessibility and SEO are not competing goals — they reinforce each other.
Does WCAG also apply to mobile apps?
Yes. The WCAG 2.x generally also apply to mobile web apps. For native apps (iOS, Android), there are additionally the WCAG 2.1 extensions and the mobile accessibility guidelines of the respective platforms (Apple Accessibility, Android Accessibility). The BFSG explicitly includes mobile applications that are classified as digital services.
Can an AI chatbot be accessible?
Yes — if it is designed for that from the beginning. Key aspects include: complete keyboard navigation, ARIA live regions for dynamically generated responses, sufficient color contrasts, descriptive labels for all interactive elements, and the ability to close the chat at any time using the keyboard. Branchly meets these requirements by default. The 5–10% interaction rate (vs. 0.5–1% industry average) shows that accessible design and high user engagement are not contradictory.
What is the difference between WCAG, BITV, and BFSG?
The WCAG are the international standard (W3C). The BITV 2.0 (Barrier-Free Information Technology Ordinance) is the German implementation for public bodies and references WCAG 2.1 AA. The BFSG (Accessibility Enhancement Act) is the German implementation of the European Accessibility Act, applying since June 28, 2025, to private companies — also based on WCAG 2.1 AA (via EN 301 549).
