Ask what would be missing
Imagine removing the image from the page. What information would a reader lose? That question is a better starting point than naming every visible object. A project screenshot might demonstrate a dashboard’s filter layout, while an abstract shape behind the title contributes no information at all. Their alternative text should not be treated the same way.
Describe informative images concisely
A useful description explains the relevant content in context. On a case study about a responsive checkout, an image might be described as Mobile checkout with delivery details above the payment summary. The goal is not an exhaustive visual inventory. Focus on the detail the surrounding discussion expects the reader to notice.
Give decorative images an empty alternative
For an img that is purely decorative, an empty alt attribute allows assistive technology to skip it. Omitting alt is a different choice and can expose an unhelpful filename in some contexts. CSS background decoration usually does not need a text alternative, but it must not carry information that is otherwise absent from the page.
Consider the surrounding link
When an image is the only content of a link, its alternative needs to communicate the link’s purpose. If a project card already includes a clear text title in the same link, repeating that entire title as image alt may create a redundant name. Review the accessible name of the complete interactive element, not the image in isolation.
Handle charts and text-heavy images differently
A chart may need a concise image alternative plus a nearby explanation or data table. A screenshot containing important instructions should not be the only place those instructions appear. Where possible, use real text for headings, labels and explanatory content. A very long alt attribute is not an effective substitute for a structured explanation.
Review without looking at the picture
Read the title, image alternative and nearby paragraph aloud as one sequence. Remove duplicated information and irrelevant phrases. Check that filenames, target keywords and generic descriptions such as beautiful image have not replaced useful meaning. Alt text succeeds when someone can understand the image’s contribution to the page without having to see it.
Further reading
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