Image Alt Check

Why It Matters

• Screen reader users depend on it. For users who cannot see images, the alt text is the only way to know what an image shows. Missing alt text means missing information — or worse, a screen reader announcing a meaningless filename.
• Search engines use alt text to understand images. Crawlers cannot "see" images. They rely on alt text to figure out what the image depicts and whether it is relevant to the surrounding content and search queries.
• It catches images you forgot about. Over time, pages accumulate images through CMS updates, template changes, and content edits. A systematic check finds images without alt text that you did not even know existed.
• Decorative images need handling too. An alt check is not just about adding descriptions — it is also about correctly marking decorative images with empty alt attributes so they do not clutter the screen reader experience.

How to Do It

1. Check every image for an alt attribute. Open your page source or use browser developer tools to find all <img> tags. Every single one should have an alt attribute — no exceptions.
2. Decide if the image is informative or decorative. Does the image convey information that is not available in the surrounding text? If yes, it needs a meaningful description. If it is purely decorative (a background pattern, a spacer, an ornamental border), give it alt="".
3. Write concise, descriptive alt text for informative images. Describe what the image shows in a sentence or short phrase. "A red bicycle parked against a brick wall" is good. "Image" or "photo" is not.
4. Check background images and CSS images. Images loaded via CSS background-image do not have alt attributes. If they carry meaning, consider using an aria-label or replacing them with proper <img> tags.
5. Review regularly, not just once. Content changes constantly. Make image alt checks part of your regular content review process so new images do not slip through without proper alt text.

Common Mistakes

• Missing the alt attribute entirely. An image without any alt attribute at all is worse than an empty one. Screen readers may announce the filename (like "IMG_2847.jpg"), which is confusing and unhelpful.
• Using generic text like "image" or "photo." Alt text that says "image" describes nothing. The user already knows it is an image — they need to know what it shows.
• Giving decorative images a description. A decorative divider does not need alt text like "decorative line." That just adds noise for screen reader users. Use alt="" so it is skipped entirely.
• Only checking once at launch. If you only review alt text when the site launches and never again, new images added over months and years will accumulate without proper alt text.