The number that surprised us
Our site had 41 images. Only 3 had alt text. That's 7% coverage. Every AI system that reads raw HTML instead of rendering it visually saw a page that was, for all practical purposes, mostly blank in its visual sections, including our own case studies.
This isn't a rare mistake. It's the default state of most sites built quickly, because alt text is invisible to the person building the page and invisible to visitors. It's only visible to search engines, screen readers, and now, AI systems trying to understand what's actually on your page.
What this actually costs you
Missing alt text doesn't just hurt accessibility, though it hurts that too. It means:
- Search engines can't confirm what your images show, so they can't use them as ranking or relevance signals.
- AI answer engines summarizing your page skip your visual proof entirely, your work samples, your team photos, your product shots.
- If a screen reader user visits your site, entire sections effectively don't exist for them.
The fix is not complicated, just tedious
Every real, non-decorative image needs one honest sentence describing what it shows. Not keyword-stuffed, not generic ("image1.jpg" renamed to "seo-image"), just accurate. "Optical People booking flow on mobile" beats "screenshot" every time.
Schema markup matters just as much
While we were fixing alt text, our audit also confirmed something worth knowing: a single, correct H1, valid schema.org structured data, and a canonical tag were already in place on our site. Those three things are just as important as alt text for AI visibility, they're the machine-readable skeleton of a page. If you have good structure but weak alt text, you're halfway there. If you have neither, an AI system has almost nothing reliable to work with.
FAQ
Does alt text actually affect AI search visibility, or just accessibility?Both. Alt text is one of the only ways an AI system that doesn't render images can understand what's on your page, especially in visual-heavy sections like case studies or product galleries.
What's a realistic alt-text coverage target?Every meaningful image should have it. Purely decorative images (background textures, spacers) can be skipped, but anything showing real content, work, people, or products should always have accurate alt text.
How do I check my own site's alt-text coverage?Run it through a free audit tool like ours at twodoorsdigital.com, it checks alt-text coverage, schema markup, and canonical tags in about 30 seconds.
Curious where your own site is leaking? Run the free pipeline audit and see your real numbers, not a guess.


