Digital accessibility is no longer optional: it’s a requirement. Whether to comply with legal obligations, improve user experience, or strengthen brand credibility, making a website accessible benefits everyone.
At the heart of this approach lie the WCAG (Web Content Accessibility Guidelines) - the international standard that defines how to design web content usable by as many people as possible, including those with disabilities.But understanding WCAG compliance levels (A, AA, AAA) can quickly get complex. What do they mean? What’s the difference between minimal compliance and a truly inclusive website?
And how can you concretely assess your level of compliance?This article, written by HubSpot experts, helps you understand the foundations and levels of WCAG compliance, identify best practices to implement, and make connections with other standards such as RGAA in France or PDF/UA for digital documents.
Digital accessibility is no longer optional: it’s a requirement. Whether to comply with legal obligations, improve user experience, or strengthen brand credibility, making a website accessible benefits everyone.
At the heart of this approach lie the WCAG (Web Content Accessibility Guidelines) - the international standard that defines how to design web content usable by as many people as possible, including those with disabilities.But understanding WCAG compliance levels (A, AA, AAA) can quickly get complex. What do they mean? What’s the difference between minimal compliance and a truly inclusive website?
And how can you concretely assess your level of compliance?This article, written by HubSpot experts, helps you understand the foundations and levels of WCAG compliance, identify best practices to implement, and make connections with other standards such as RGAA in France or PDF/UA for digital documents.
The WCAG are built on four key principles, often summarized by the acronym POUR:
Perceivable – Information and components must be perceivable by everyone, regardless of their access method (visual, auditory, tactile).
Operable – The interface should be navigable through multiple devices, including keyboard, voice commands, or screen readers.
Understandable – Content and navigation should be clear, consistent, and predictable.
Robust – The site must remain compatible with both current and future assistive technologies.
Together, these pillars ensure a site is not just visible - but truly usable and inclusive.
WCAG compliance isn’t a box-ticking exercise. It serves three major purposes:
Human – It ensures a fair, equal experience for all users, including those with visual, auditory, motor, or cognitive disabilities.
Legal – In many countries (including France via the RGAA), compliance is mandatory for public websites and strongly encouraged for private organizations.
Strategic – An accessible website provides a smoother user experience, better SEO, and a stronger brand image.
In other words, accessibility isn’t a constraint - it’s a performance and inclusion driver.
WCAG defines three compliance levels - A, AA, and AAA - each representing a different depth of accessibility, from foundational to exceptional.
Level A is the baseline for accessibility.
It covers essential requirements to make a site usable for most people with disabilities, such as:
Keyboard navigation without using a mouse
Alternative text for images
Avoiding flashing or disruptive elements
This level ensures basic technical accessibility - but the user experience may still fall short for many visitors.
Level AA is the industry benchmark - the standard most organizations aim to reach.It includes all Level A criteria and adds more advanced requirements around readability, color contrast, navigation consistency, and comprehension.
A Level AA-compliant site provides an inclusive experience for a wide range of users, including those with moderate visual or cognitive impairments.It’s also the legal requirement under the French RGAA for public websites and the recommended goal for private companies.
Level AAA represents the highest level of accessibility excellence.It includes all Level A and AA requirements, plus advanced criteria such as:
Full audio descriptions for videos
Sign language versions for audio content
Highly customizable interfaces (text size, color contrast, etc.)
While achieving AAA across an entire site can be challenging, it’s often applied to key pages or features - particularly those aimed at sensitive or institutional audiences.Reaching this level demonstrates a strong ethical and inclusive commitment.
Accessibility isn’t a one-off project - it’s an ongoing process. Testing, fixing, and improving accessibility should be embedded in your digital strategy.
Effective accessibility audits combine two complementary approaches:
Automated testing – Tools like WAVE, axe DevTools, or Pa11y quickly flag technical issues such as missing alt text or insufficient contrast.
Manual testing – Conducted by experts or users with disabilities to assess real-world usability, navigation logic, and comprehension barriers that automation can’t catch.
The best approach blends both: automation for speed, human testing for true inclusivity.
Reaching compliance is only the beginning. To make it last:
Integrate accessibility from the design stage – Considering WCAG early prevents costly rework later.
Train your teams – Writers, designers, and developers should all understand accessibility principles.
Schedule regular audits – Yearly or semi-annual reviews help detect regressions.
Document your standards – Keep an internal accessibility guide to ensure consistency across projects.
The goal isn’t just to comply - it’s to make accessibility part of your company culture.
WCAG (Web Content Accessibility Guidelines) – The international W3C standards for accessible web content.
RGAA (Référentiel Général d’Amélioration de l’Accessibilité) – The French adaptation of WCAG, aligning the same principles with the country’s legal framework and making them mandatory for public websites.
PDF/UA (ISO 14289) – The standard for accessible PDFs, ensuring documents are readable and navigable with assistive technologies like screen readers or keyboard navigation.
In short:
WCAG → Global web accessibility standards
RGAA → French legal version of WCAG
PDF/UA → Accessibility standard for PDF files
All share the same purpose: making digital content accessible and inclusive for everyone.
WCAG is the global foundation of digital accessibility.
Understanding and implementing its principles helps you go beyond legal compliance - creating a better, more inclusive experience for every visitor.
Achieving compliance is an investment in your website’s quality, reliability, and brand trust.
What are the four core principles of WCAG?
Perceivable – Content must be perceivable by all users.
Operable – Users must be able to interact using various input methods (keyboard, mouse, screen reader).
Understandable – Navigation and content must be clear and predictable.
Robust – The site should work seamlessly with assistive technologies now and in the future.
What are the WCAG compliance levels?
A – The minimal level, ensuring basic access to content.
AA – The recommended standard for most organizations.
AAA – The highest level, offering maximum accessibility for specific use cases.
What’s the difference between WCAG and PDF/UA?
WCAG applies to web content (sites, apps, e-learning), while PDF/UA applies to PDF documents.
Both aim to make content accessible to people with disabilities, but they differ in scope and technology - HTML/JavaScript for WCAG, PDF structure and tagging for PDF/UA.