Where the two align.
WHAT HELPS BOTH
Alt text on images Clear heading structure Descriptive link text Proper page titles Semantic markup Text rather than images of text Fast loading Mobile usability Captions and transcripts for video
WHY THEY OVERLAP
Search engines and assistive technology both read the page without seeing it.
Structure that helps one helps the other.
WHERE THEY DIFFER
Accessibility cares whether a keyboard user can reach a control. Search engines do not.
Search cares about content quality and links. Accessibility does not.
THE PRACTICAL POINT
Much accessibility work produces search benefits without additional effort.
That is a reasonable argument for doing it, and it is not the main reason.
WHAT NOT TO DO
Treat alt text as a keyword opportunity. It reads terribly aloud and it does not help search.
Describe the image.
THE HONEST FRAMING
Do accessibility because people need it. Mention the search benefit when persuading someone who needs persuading.
