Alt text is one of those SEO topics that feels settled—almost boring—until you look at how it’s actually used on real sites.
Most people treat it as a box to fill. A compliance task. Something you do because a checklist says so, not because it meaningfully improves anything. And that’s exactly why alt text quietly underperforms on so many otherwise well-optimized pages.
The problem isn’t that alt text doesn’t matter.
It’s that people misunderstand what it’s for and when it matters.
What alt text is really doing (beyond the obvious)
Yes, alt text helps with accessibility. That part is non-negotiable and well-documented.
But from an SEO perspective, alt text plays a narrower, more contextual role than most guides admit. It’s not a ranking lever in the traditional sense. It’s a clarification signal.
Alt text exists to explain an image when the image itself can’t. That could be because:
- The user can’t see it
- The image doesn’t load
- Google needs textual confirmation of what the image represents
The mistake is assuming this explanation should always be keyword-focused.
In practice, the best alt text is rarely written for search engines. It’s written so precisely that search engines don’t need to guess.
Where alt text actually influences SEO
Alt text tends to matter in three specific situations:
- Images that carry meaning
Diagrams, charts, product images, instructional visuals—anything where the image adds information not already obvious from the surrounding text. - Image search visibility
If image traffic matters to you, alt text becomes one of the few direct inputs Google has. But even here, relevance beats optimization. - Context reinforcement
Alt text can subtly reinforce topical relevance when it aligns naturally with the page’s subject. Not by repeating keywords, but by describing what’s genuinely there.
Outside of these cases, alt text rarely moves the needle on its own.
That’s why sites with thousands of “SEO-optimized” alt attributes often see no measurable impact.
The over-optimization trap (and why it’s so common)
Alt text is an easy place to stuff keywords because it feels invisible. Users don’t see it. Designers don’t object. CMSs don’t warn you.
So you end up with things like:
“Best digital marketing agency SEO services India affordable”
That’s not alt text. That’s anxiety.
Google is good at detecting when text exists for machines, not humans. Alt text is no exception. When it stops describing the image and starts advertising the page, it loses its value entirely.
In some cases, it can even introduce confusion—especially when the visible content and alt text tell different stories.
When not to use alt text aggressively
Not every image needs descriptive alt text.
Decorative images, background visuals, icons used purely for UI—these don’t benefit from verbose descriptions. Adding them often creates noise, not clarity.
Empty alt attributes (alt="") are sometimes the correct choice. That’s not neglect. That’s intent.
The goal isn’t maximum coverage. It’s accurate signaling.
What good alt text looks like in practice
Good alt text is boring in the best way.
It:
- Describes what’s actually in the image
- Matches the surrounding context
- Stops once the image is clearly understood
If the page already explains the image in detail, alt text should complement—not repeat—it.
If you wouldn’t naturally say the sentence out loud to explain the image to someone, it probably doesn’t belong in the alt attribute.
The mistake that causes real problems
The most damaging alt text mistake isn’t keyword stuffing. It’s scale without thought.
Auto-generated alt text across thousands of images—based on filenames, templates, or product titles—creates systemic issues:
- Repetition
- Irrelevance
- Misleading descriptions
At that point, alt text stops being helpful and starts being misleading. And misleading signals are worse than missing ones.
How to think about alt text going forward
Alt text isn’t an SEO tactic. It’s a clarity tool.
When you treat it that way, decisions get easier:
- Important image? Describe it clearly.
- Decorative image? Don’t force it.
- Complex visual? Be precise, not clever.
Most SEO gains don’t come from adding more signals. They come from removing ambiguity.
Alt text does its job best when it quietly makes things easier to understand—for users and for search engines—without trying to prove its worth.