Web Content Accessibility Guidelines WCAG 2.1

WCAG are the international standard for accessible web content.

By referencing them in Swiss accessibility standards (e.g. eCH-0059), they are also binding in Switzerland, for example for public sector offerings. The guidelines show which requirements are placed on accessible web content so that it is accessible for users with visual, auditory, motor or cognitive impairments.

All activities of the “Access for all” foundation, from reviews to consulting to certification are always based on WCAG. All our offerings are available for WCAG 2.0 as well as 2.1 versions.

Structure of WCAG

WCAG are divided into four principles:

  • Perceivable: text alternatives for images, subtitles for audio, adaptability of the display and sufficient contrasts.
  • Operable: keyboard operability, sufficient time for inputs, prevention of seizures, and navigability
  • Understandable: readability, predictability, and aids in inputting
  • Robust: compatibility with assistive technologies

Success criteria

WCAG contain 78 so-called success criteria. 17 of these were added in version 2.1 of WCAG, 61 were already present in WCAG 2.0. The success criteria are divided into three conformance levels, reflecting their priority:

  • Level A: basic accessibility requirements, highest priority
  • Level AA: medium priority requirements
  • Level AAA: additional requirements of lower priority

Commonly, level A and AA criteria are required, for example, for government offerings.

WCAG 2.0 vs. WCAG 2.1

WCAG 2.0 were published in 2008 by the W3C as a standard for accessible web content. They have proven to be a very adequate set of requirements for accessible content for almost 10 years and were only extended to a version 2.1 in 2018. Thereby, all requirements of WCAG 2.0 have been adopted unchanged. The additions relate to the areas of visual disabilities, cognitive impairments and mobile use. For example, contrast requirements are now also placed on control elements and informative graphic elements (not only on text against a background). Also, web content may not be controlled exclusively by certain gestures or by moving a device.

Further sources