Somewhere around 2019, an SEO blog post told the internet to stuff alt text with keywords. "Best running shoes cheap sale 2026 buy now," typed straight into the alt attribute of a single product photo. The advice felt clever at the time. It was already wrong the moment it went out.
That original post is long gone, but the habit never left. Style guides still repeat it. Content teams still do it because it's "how we've always written alt text." Meanwhile two very different groups of people quietly pay the price: a screen reader user who gets a garbled sentence instead of a description, and a search engine that now reads stuffed alt text for exactly what it is, spam.
Here's the part nobody explains when they hand you that old advice: fixing this for accessibility and fixing it for search turn out to be the same fix.
The Stat: More than 1 in 4 images on popular home pages have missing, questionable, or repetitive alt text. (Source: WebAIM Million, 2026)
The advice that should have died in 2019
Alt text was never designed as a place to rank for a keyword. It exists under WCAG 1.1.1 Non-text Content, a Level A success criterion, and the requirement is narrow and specific: the alt text has to serve an equivalent purpose to the image. Not related words. Not a phrase that might drive traffic. An equivalent.
"Best running shoes cheap sale 2026 buy now" is not equivalent to a photo of one specific shoe. It's a sentence built for an algorithm that stopped rewarding this behavior a long time ago. Google's own official guidance on writing helpful alt text is explicit that image alt text should be short, accurate, and descriptive of the actual image, not a container for extra keywords. The SEO upside people chase with keyword stuffing hasn't existed for years. What's left is only the downside.
What a screen reader user actually hears
Picture a screen reader user shopping for shoes. They land on a product image and their screen reader speaks whatever sits in the alt attribute. If that text is "best running shoes cheap sale 2026 buy now," they hear a run-on marketing phrase that tells them nothing about the actual product in front of them: not the color, not the style, not what makes this pair different from the one on the next tab.
Compare that to "Grey running shoe with red sole, side view." That's a description a sighted shopper gets for free just by looking at the photo, and now a screen reader user gets it too. That's the entire point of SC 1.1.1: parity of information, not a marketing slogan wedged into a place it doesn't belong.
The AI autogeneration trap
A lot of teams think they've already solved this by handing the job to an AI image-captioning tool and moving on. That's progress over keyword stuffing, but it isn't the fix people assume it is. A 2026 CHI paper found that AI-generated image descriptions actually reduced real screen reader task completion rates compared to human-written descriptions, because the AI descriptions emphasized the wrong details. Instead of naming the one thing a user needed to complete their task (which button, which product, which chart value), the generated captions drifted toward mood, composition, or generic scene description.
It's a different cause than keyword stuffing, but it's the same failure mode: alt text that describes something other than what the user actually needed from that image, in that context, to do the thing they came to do.
The one rule that fixes both problems
Here's the rule, and it's genuinely one rule: describe what the image shows or does, specific to its purpose on that page, and stop there.
That single standard satisfies WCAG 1.1.1 because it produces an equivalent, and it satisfies modern search guidance because it produces exactly what Google says it wants: real, accurate, concise description instead of keyword noise.
| Image type | Bad alt text (keyword-stuffed) | Good alt text (descriptive) |
|---|---|---|
| Product photo | "best running shoes cheap sale 2026 buy now" | "Grey running shoe with red sole, side view" |
| Blog header image | "seo tips accessibility guide free download 2026" | "Illustration of a magnifying glass over a webpage" |
| Company logo | "best accessibility company software solutions" | "Company name" |
| Functional icon (e.g. search button) | "click here search now find results fast" | "Search" |
| Purely decorative image | "background pattern design decoration" | alt="" (empty, marked decorative) |
A short checklist if you're auditing a page right now:
- Does the alt text describe what's actually in the image, not what you wish it ranked for?
- Would it make sense read aloud, on its own, with no visual context?
- Is it specific enough to distinguish this image from a similar one on the same page?
- Is genuinely decorative imagery marked with an empty
alt=""instead of a fake description? - Have you skipped any AI-generated captions without checking whether they name the actually relevant detail?
If you want the line-by-line version of this, read our deeper guide to writing alt text that actually works. And if you'd rather just see where your own pages currently stand, you can check your images with our free tools before anything else changes.
Fixing alt text isn't a redesign and it isn't a rewrite of your content strategy. It's a pass over your images with one clear rule instead of an outdated one. That's exactly what our free alt text tools are built to help with, so you can see, image by image, what a screen reader hears and what a search engine actually rewards, before either one quietly costs you.