Try it yourself
Four images from a bakery's website. Alt text is read aloud to people using a screen reader, and shown when an image fails to load.
Which alt text actually does its job?
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Empty alt is correct for an image that is purely decorative — it tells a screen reader to skip it. On a main photo that shows the product, it throws information away.
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Worse than empty. A screen reader announces "image, image", and the listener learns nothing at all.
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This is the one. It describes what is in the picture, in a sentence someone would actually say. If the image never loads, the sentence still carries the meaning.
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Keywords stuffed into an accessibility feature. It is unpleasant to listen to and it is the kind of thing search engines learned to discount a long time ago.
Pick a line. Every one of them has an answer.
Show me the answer
<img src="hero.jpg" alt="Sourdough loaves cooling on a rack in the shop window">
This is the one. It describes what is in the picture, in a sentence someone would actually say. If the image never loads, the sentence still carries the meaning.
The written version
Alt text: describing an image to someone who cannot see it →
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