Definition
Alt text (short for “alternative text”) is a brief written description assigned to images on a web page using the HTML alt attribute. It serves two primary purposes: providing context to users who are visually impaired and depend on screen readers, and improving SEO by helping search engines understand the content and relevance of images within a web page.
Alt text is not typically visible on the webpage itself. Instead, it’s embedded in the page’s code and accessed by screen readers or displayed in place of an image if it fails to load. A well-written alt attribute should describe the contents and function of the image succinctly and accurately.
Is It Still Relevant?
Yes, alt text remains highly relevant in both accessibility and SEO. As of recent Google algorithm updates, including the helpful content update and ongoing emphasis on user experience (UX) and accessibility, alt text continues to play a vital role in how content is evaluated and ranked.
From an SEO perspective, Google Image Search has become a significant discovery channel. Properly optimized alt text increases image visibility in search results, driving additional organic traffic. Moreover, compliance with accessibility standards such as WCAG (Web Content Accessibility Guidelines) and laws like the Americans with Disabilities Act (ADA) has made the use of alt text a legal and ethical necessity.
Real-world Context
Consider an eCommerce website selling running shoes. Each product page contains several images—shoes from different angles, close-ups, color variations, and so on. By including meaningful alt text like “Men’s lightweight blue running shoes with breathable mesh upper” instead of something generic like “shoe1.jpg,” the site:
– Makes product images accessible to visually impaired users,
– Enhances the site’s SEO by giving search engines relevant image context,
– Improves the likelihood of images appearing in Google Images search results.
Similarly, blog content that uses infographics or graphs can include descriptive alt text summarizing the insights the image conveys, ensuring users relying on screen readers still gain value from visual content.
Background
The concept of alt text originated in the early days of HTML—specifically HTML 2.0—when the web was being structured to support a variety of user agents, including those without graphical displays. The alt attribute was included as a fallback mechanism to describe images that didn’t render, either due to browser limitations or slow internet connections.
With the formalization of accessibility standards in the 2000s and the rise of mobile and assistive browsing technologies, alt text evolved from a basic fallback tool to a cornerstone of accessible web design. At the same time, search engines began parsing alt attributes to understand page content better and rank visuals appropriately.
What to Focus on Today
To leverage alt text effectively in today’s digital marketing environment, consider the following best practices:
– Be descriptive but concise: Focus on what the image depicts and how it relates to the content. For example, instead of writing “image” or “chart,” describe it: “Bar chart showing monthly sales growth from January to June.”
– Incorporate relevant keywords naturally: If appropriate, include SEO keywords, but avoid keyword stuffing or irrelevant terms.
– Avoid redundant phrases: Do not start with “image of” or “picture of”—screen readers already recognize it as an image.
– Don’t use alt text for decorative images: If an image doesn’t convey essential information, use an empty alt attribute (alt=””) so screen readers can skip it.
– Use tools and audits: Platforms like Google Lighthouse, WAVE, and SEMrush can help identify missing or under-optimized alt attributes across your site.
In our increasingly visual and inclusive digital landscape, alt text continues to serve double duty—enhancing accessibility and boosting SEO—making it essential for any modern web strategy. Embrace it not just as a technical checkbox but as a meaningful way to create a more inclusive and visible web presence.