{"id":70873,"date":"2025-12-17T23:24:40","date_gmt":"2025-12-17T23:24:40","guid":{"rendered":"https:\/\/www.arimetrics.com\/glosario-digital\/web-accessibility"},"modified":"2026-09-28T07:09:41","modified_gmt":"2026-09-28T07:09:41","slug":"web-accessibility","status":"publish","type":"encyclopedia","link":"https:\/\/www.arimetrics.com\/en\/digital-glossary\/web-accessibility","title":{"rendered":"Web Accessibility"},"content":{"rendered":"<p><img decoding=\"async\" class=\"boxpad alignright wp-image-80347 size-full\" src=\"https:\/\/www.arimetrics.com\/wp-content\/uploads\/2026\/09\/web-accessibility.jpg\" alt=\"Web accessibility\" width=\"300\" height=\"300\" srcset=\"https:\/\/www.arimetrics.com\/wp-content\/uploads\/2026\/09\/web-accessibility.jpg 300w, https:\/\/www.arimetrics.com\/wp-content\/uploads\/2026\/09\/web-accessibility-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><strong>Definition:<\/strong><\/p>\n<p><strong>Web accessibility<\/strong> is the discipline of designing, developing, writing and maintaining websites, applications and web content so that people with disabilities can perceive, understand, navigate and interact with them. It covers visual, auditory, physical, speech, cognitive and neurological disabilities and considers assistive technologies such as screen readers, magnifiers, switches and voice recognition.<\/p>\n<p>Its purpose is to identify and reduce digital barriers. It can also benefit people with temporary or situational limitations, but its primary aim is to ensure that disability does not prevent someone from accessing information or completing a task.<\/p>\n\n<h2>What web accessibility covers<\/h2>\n<p>Accessibility depends on several layers working together: structure, presentation, content and interaction. A page may include alternative text and still be inaccessible if a menu cannot be operated with a keyboard, focus is not visible or a form does not communicate its errors.<\/p>\n<p>The <a href=\"https:\/\/www.w3.org\/WAI\/fundamentals\/accessibility-intro\/\" target=\"_blank\" rel=\"noopener\">W3C introduction to web accessibility<\/a> explains that people must be able to perceive, understand, navigate and interact with the web. This scope includes pages, documents, media players, forms, dynamic components and complete processes such as registering, purchasing or booking an appointment.<\/p>\n<p>Accessibility does not mean providing a separate simplified version. The preferred approach is to integrate accessibility requirements into the design, content and code of the main product so that it works with different devices, settings and assistive technologies.<\/p>\n<h2>POUR principles and WCAG<\/h2>\n<p>The <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/w3c\">W3C<\/a>, through the Web Accessibility Initiative, develops the Web Content Accessibility Guidelines (WCAG). These guidelines are organized around four principles known as POUR:<\/p>\n<ul>\n<li><strong>Perceivable:<\/strong> Information must be presented in forms people can perceive, for example through text alternatives, captions, sufficient contrast and adaptable content.<\/li>\n<li><strong>Operable:<\/strong> The interface must work with a keyboard and other input methods, provide enough time and avoid content that causes physical reactions.<\/li>\n<li><strong>Understandable:<\/strong> Content and interaction must be readable, predictable and able to help people prevent or correct errors.<\/li>\n<li><strong>Robust:<\/strong> Markup must communicate names, roles, states and relationships correctly to browsers and assistive technologies.<\/li>\n<\/ul>\n<p>WCAG turns these principles into testable conformance criteria and groups them into levels A, AA and AAA. A conformance statement must identify the level, version and evaluated scope; passing selected checks does not by itself establish that an entire site conforms.<\/p>\n<h2>Common barriers<\/h2>\n<p>Barriers arise when content or an interface depends on only one way of perceiving or acting. Common examples include:<\/p>\n<ul>\n<li><strong>Images without an alternative:<\/strong> The <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/alt-attribute\">alt attribute<\/a> should convey the image&#8217;s function or information when it is needed.<\/li>\n<li><strong>Video or audio without an equivalent alternative:<\/strong> Captions, transcripts and audio descriptions make content available through other channels.<\/li>\n<li><strong>Insufficient contrast or size:<\/strong> Text, controls and focus indicators must remain distinguishable under different viewing conditions.<\/li>\n<li><strong>Mouse-dependent navigation:<\/strong> Links, menus, dialogs and forms must work with a keyboard without losing focus or trapping the user.<\/li>\n<li><strong>Weak semantic structure:<\/strong> Headings, landmarks, lists, labels and native controls help communicate the organization and purpose of content.<\/li>\n<li><strong>Ambiguous forms:<\/strong> Each field needs a clear label, understandable instructions and error messages that identify the problem and how to correct it.<\/li>\n<li><strong>Unannounced dynamic content:<\/strong> State changes must be communicated when they are not evident to assistive technology. ARIA supplements native HTML when it cannot express the required semantics.<\/li>\n<\/ul>\n<p><a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/responsive\">Responsive design<\/a> can improve adaptation to different screens, but it does not replace requirements such as focus order, content reflow or text resizing.<\/p>\n<h2>Evaluation and conformance<\/h2>\n<p>A reliable evaluation combines methods. Automated tools detect certain code or contrast failures, but they cannot determine on their own whether alternative text is useful, the reading order makes sense or a process can be completed.<\/p>\n<p>The process usually includes these checks:<\/p>\n<ol>\n<li><strong>Automated review:<\/strong> Finds detectable patterns and helps repeat checks across templates and components.<\/li>\n<li><strong>Manual inspection:<\/strong> Reviews structure, zoom, reflow, contrast, multimedia, forms, errors and changes of context.<\/li>\n<li><strong>Functional testing:<\/strong> Completes full tasks with a keyboard and technologies such as NVDA, JAWS, VoiceOver or magnifiers.<\/li>\n<li><strong>Testing with people with disabilities:<\/strong> Reveals real-world barriers that a technical review may not anticipate.<\/li>\n<\/ol>\n<p>The sample, pages, states and processes assessed should be documented. Accessibility also requires maintenance: a new component, campaign or content change can introduce barriers even when the template was reviewed previously.<\/p>\n<h2>Accessibility, usability, SEO and regulation<\/h2>\n<p>Accessibility and <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/usability\">usability<\/a> are related but not equivalent. Usability examines effectiveness, efficiency and satisfaction, while accessibility requires people with disabilities to be able to access and interact. Both contribute to a complete <a href=\"https:\/\/www.arimetrics.com\/en\/digital-glossary\/ux\">user experience<\/a>.<\/p>\n<p>Some accessible practices, such as clear semantic structure and useful text alternatives, also help systems interpret content. This overlap does not make WCAG conformance an automatic ranking factor or guarantee traffic, conversions or loyalty.<\/p>\n<p>Legal duties depend on the country, sector, organization and service. In the European Union, the Web Accessibility Directive applies to public-sector websites and apps, while the European Accessibility Act covers specified private-sector products and services. WCAG and the European standard EN 301 549 are used as technical references, but legal compliance must be assessed against the applicable scope.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Definition: Web accessibility is the discipline of designing, developing, writing and maintaining websites, applications and web content so that people with disabilities can perceive, understand, navigate and interact with them. It covers visual, auditory, physical, speech, cognitive and neurological disabilities and considers assistive technologies such as screen readers, magnifiers, switches and voice recognition. Its purpose [&hellip;]<\/p>\n","protected":false},"author":36,"featured_media":0,"template":"","encyclopedia-tag":[1428],"class_list":["post-70873","encyclopedia","type-encyclopedia","status-publish","hentry","encyclopedia-tag-web-accessibility"],"_links":{"self":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia\/70873","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia"}],"about":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/types\/encyclopedia"}],"author":[{"embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/users\/36"}],"wp:attachment":[{"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/media?parent=70873"}],"wp:term":[{"taxonomy":"encyclopedia-tag","embeddable":true,"href":"https:\/\/www.arimetrics.com\/en\/wp-json\/wp\/v2\/encyclopedia-tag?post=70873"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}