←  All terms
W
Accessibility

WCAG

The Web Content Accessibility Guidelines are the W3C's international standard for accessible web content with testable success criteria.

The Web Content Accessibility Guidelines provide a structured framework for making digital content more accessible, with defined principles and testable success criteria. In practice, accessibility work should rely on native web standards wherever possible and combine automated testing with manual checks using a keyboard and assistive technologies. The concept is closely related to Web Accessibility and EN 301 549.

Read more

Web Accessibility

EN 301 549

ARIA

Color Contrast

FAQ

WCAG

What contrast values does WCAG require for text and controls?
Normal text needs a contrast ratio of at least 4.5:1, while large text as well as interface controls and graphical objects need at least 3:1. Text counts as large from 18 pt, or 14 pt bold. These values correspond to WCAG 2.1 AA. Good contrast alone does not make a page accessible, though.
Are automated tests enough to establish WCAG conformance?
No, automated tests catch only part of the problems. They detect missing alt text or insufficient color contrast, but they cannot judge whether an interaction is understandable or a focus order makes sense. Manual checks with a keyboard and a screen reader therefore remain mandatory.
Which four principles are WCAG based on?
WCAG rests on four principles: perceivable, operable, understandable, and robust. Every success criterion maps to one of them. They work as a mental model: content must be recognizable, controllable by keyboard, comprehensible in its behavior, and compatible with a range of technologies.
Which WCAG version applies, 2.1 or 2.2?
Versions 2.1 and 2.2 both exist, and 2.2 builds on 2.1 with additional success criteria. Which one is binding depends on the applicable regulation or project requirement. For new projects, 2.2 is the natural choice because it reflects the current state of the guidelines.
What do conformance levels A, AA, and AAA mean?
The levels grade the success criteria by demand: A is the baseline, AA the usual target, and AAA the most extensive level. AAA is rarely pursued for entire websites because some criteria cannot be met for all types of content. In practice and in many requirements, AA is the reference point.
How do WCAG and web accessibility differ?
Accessibility is the goal, while WCAG is a yardstick that makes it testable. The guidelines cover web content but do not guarantee good usability for every person. A site can meet the criteria on paper and still create barriers in daily use, which is why testing with a keyboard and assistive technologies remains necessary.