What this means in practice
Alt text describes the meaningful function or information of an image for people who cannot perceive it. It is primarily an accessibility feature, with secondary relevance to image understanding.
Why this matters: Describe the image’s relevant purpose or information concisely. Decorative images can often use empty alt text so assistive technology can skip them.
Implementation path
- Write concise alt text that conveys the image’s purpose in the page context, not every visible detail.
- For decorative images, use an empty alt attribute so assistive technology can skip them.
- Do not stuff keywords into alt text or repeat captions that already provide the same information.
- Test images with the surrounding content: the alternative should still make sense when the image itself is unavailable.
What good looks like
A strong implementation makes the intended behavior obvious to a visitor, a crawler, and a machine reader. It has one clear purpose, uses consistent signals, and does not rely on hidden assumptions.
SEOIntent, discoverability, metadata, internal links, crawlability, and indexability are aligned with this topic.
AEOThe page answers the core question early and uses descriptive sections so important information is easy to extract.
GEOKey entities, claims, scope, and relationships are explicit enough to be interpreted outside the page context.
UXThe page is readable on mobile, keyboard-friendly, visually structured, and clear about the next useful action.