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Alt text 0:34
A 34-second explainer of Alt text, narrated over the same demo you can try yourself.
Try the interactive Alt text demo
What this video covers
Alt text is a text alternative that explains an image’s purpose or meaning within its context. Decorative images should use empty alt text; complex images may require a longer description elsewhere.
With no alt the screen reader had nothing useful to say; with the filename it read out gibberish; with a real description it passed on the actual point of the picture. Same image every time - the only thing that changed was whether someone not looking at it got the meaning or got left out.
