ALT tags (also known as alt text) are descriptive attributes added to image elements that convey the content and purpose of an image to users who cannot see it—such as those relying on screen readers or browsing with images disabled. In 2026 and 2027, ALT tags remain critical for accessibility compliance (including the EAA and Section 508), search engine optimization, and supporting AI-powered image analysis tools like Alt Audit.
Originally, “alt text” emerged when web browsers weren’t universally graphical; it served as a fallback description for non-visual browsers. Today, ALT tags are far more than basic descriptors. They are a foundational component of inclusive web design, enabling equitable access for over 1 billion people with visual impairments globally[1][3].
Modern best practices emphasize that ALT text should be concise (ideally under 125 characters), context-aware, and purpose-driven—not just a visual description. For example, describe what the image shows and why it matters on this specific page[1][2]. Avoid starting with “Image of” or “Photo of”—screen readers already announce the element as an image[1][3].
ALT tags also integrate seamlessly with AI tools that generate context-aware descriptions at scale, flagging images requiring human review for accuracy and nuance[1][6]. Whether you’re handling product images, charts, icons, or screenshots, tailoring ALT text to the image’s function ensures both accessibility and discoverability[2].
Note: ALT text is not the same as a mouseover tooltip. While mouseover text appears only when interacting with a graphical element, ALT text is essential for non-visual access and must be present in the HTML for all meaningful images[1][9]. Decorative images should use alt="" (empty alt) to avoid cluttering screen reader output[1][3].