2011年12月7日 · Web Content Accessibility Guidelines (WCAG) 2.1 defines how to make Web content more accessible to people with disabilities. Accessibility involves a wide range of disabilities, including visual, auditory, physical, speech, cognitive, language, learning, and neurological disabilities.

2008年12月11日 · This page introduces the Web Content Accessibility Guidelines (WCAG) international standard, including WCAG 2.0, WCAG 2.1, and WCAG 2.2. WCAG documents explain how to make web content more accessible to people with disabilities.

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. The purpose of this guideline is to ensure that all non-text content is also available in text. "Text" refers to electronic text, not an image of text.

2024年10月9日 · WCAG standards are rooted in four main principles: perceivable, operable, understandable, and robust, often called POUR. Perceivable: Information must be perceivable to people using only one of their senses, so they understand all related content. Operable: End users must be able to interact with all webpage elements.

2025年3月13日 · Provide descriptive text for all contentful (that is, non-decorative) images and image-like elements. This includes SVG images, <img> , <canvas> , <map> , and <area> elements, as well as <input> elements where type=image and <object> elements where the type starts with image/ .

WCAG 2.1 requires a contrast ratio of at least 3:1 for graphics and user interface components (such as form input borders). WCAG Level AAA requires a contrast ratio of at least 7:1 for normal text and 4.5:1 for large text. Large text is defined as 14 point (typically 18.66px) and bold or larger, or 18 point (typically 24px) or larger.

2025年4月3日 · The WCAG guidelines are a set of recommendations for making web content more accessible developed by W3C's WAI, primarily for people with disabilities — but also for all user agents, including some highly limited devices or services, such as digital assistants.

2025年3月15日 · Web Content Accessibility Guidelines (WCAG) external link is developed through the W3C process in cooperation with individuals and organizations around the world, with a goal of providing a single shared standard for web content accessibility that meets the needs of individuals, organizations, and governments internationally.

2019年10月24日 · WCAG 2.0 has 2 additional requirements for body text links that are not underlined by default: The link text must have a 3:1 contrast ratio from the surrounding non-link text. The link must present a "non-color designator" (typically the introduction of the underline) on both mouse hover and keyboard focus.

2018年4月11日 · Understanding WCAG 2.1 provides a non-normative extended commentary on each guideline and each Success Criterion to help readers better understand the intent and how the guidelines and Success Criteria work together.