What is good alt text for a product photo?

Good alt text describes what is visible, not that something is visible

Good alt text for a product photo conveys in plain language what someone would see if the image were visible: the product type, colour, model and any features the customer needs to make a choice. "Red women's sneaker, Aria model, with white sole" works; "product photo" or "image1.jpg" does not, because it adds nothing for someone shopping with a screen reader. The text should be short and functional — no marketing language, no repetition of what is already in the product title, but the information that appears in the photo itself and nowhere else.

Not every image needs descriptive alt text. A decorative element, such as an atmosphere photo beside the actual product photo, should have empty alt text so a screen reader skips it rather than reading it aloud. For multiple photos of the same product — front, back and detail views — it helps to indicate what is different in each photo, rather than repeating the same text. An automated scan can determine whether an image has an alt attribute, but not whether its content is correct or helpful; that remains something that can only be judged by reading the text alongside viewing the photo, and that is also noted as a limitation in every scan report.

Where this comes from: WCAG 2.1, criterion 1.1.1

This requirement follows from criterion 1.1.1 (Non-text Content) of WCAG 2.1, the level AA criterion that EN 301 549 essentially amounts to in practice and which has been enforceable in all EU Member States since 28 June 2025. The criterion requires that non-text content has a text alternative that serves the same purpose — in the case of a product photo, text that gives the customer the same purchasing information as the image.