Missing alt text

Silktide finds images on your pages that have no alternative text at all. Alternative text is the written description read aloud in place of an image, so images without it are meaningless to people who cannot see them.

<!-- Problem: no alt attribute -->
<img src="apple.png">

<!-- Fixed: descriptive alt text -->
<img src="apple.png" alt="A red apple">

<!-- Also valid: explicitly decorative -->
<img src="decorative-swirl.png" alt="">

Why this matters

A has nothing to announce for an image without - at best it reads out the filename, which is rarely helpful and often confusing. People who are blind or have low vision lose whatever the image communicates, and if the image is a chart, a button, or a link, they may be unable to use the page at all.

Alt text also appears when images fail to load, and helps search engines understand your images, so fixing it benefits every visitor.

How to fix it

Add alternative text to each image in your - most have a field for it wherever you insert an image. In code, use the alt attribute as shown above.
Describe the information or purpose of the image, not its appearance. For an image that acts as a link or button, describe where it goes or what it does.
If the image is purely , give it an empty alt="" so screen readers skip it. Do not invent filler text - hearing "decorative swirl graphic" is worse than hearing nothing.

WebAIM publishes a thorough guide to writing alternative text.

How Silktide tests this

Find every image on each page.
Skip images that do not need alternative text: images with no source, images 1 pixel or smaller (usually tracking pixels), and images hidden from screen readers.
Skip images marked decorative with a role="presentation" attribute, as these are deliberately hidden from .
Report each remaining image that has no alt attribute at all.

An image with an empty alt="" passes this check but is covered by Decorative images, which asks you to confirm it is genuinely decorative. Alt text that exists but is unhelpful is covered by Weak alt text.

Troubleshooting

The image is decorative, so why is it flagged?

An image is only treated as decorative when it says so in the code, through an empty alt="" or role="presentation". An image with no alt attribute at all is ambiguous - assistive technology cannot tell "decorative" from "forgotten" - so it fails this check. Add the empty attribute to make the intent explicit.

The image comes from a third-party service

Images generated by embedded services such as maps may not be editable by you. Your website settings can exclude third-party content from this check, or you can individual findings you cannot change.