Image Alt Text too long

Very long alt text (over 125 characters) is awkward for screen readers — they read the entire string without pause, making it hard to follow.

Why it matters

Very long alt text (over 125 characters) is awkward for screen readers — they read the entire string without pause, making it hard to follow.

Schedule a fix in your next sprint. Warnings won't block your site but they consistently leave performance on the table. Estimated SEO impact: low — small marginal improvement, but cheap to fix.

How to fix

• Keep alt text concise — 8–125 characters is ideal
• Put lengthy descriptions in a caption or surrounding body text instead

Common causes

If the rule is firing across many pages, the root cause is almost always one of these:

• CMS or page builder doesn't enforce alt text at upload time, so editors leave it blank.
• Bulk-imported product images inherit a generic placeholder (or the filename) as alt.
• Theme/template renders <img> tags directly from the database without normalising attributes.
• Lazy-loading or asset pipelines strip optimisation hints during build.

Anti-patterns to avoid

Even with the best intentions, these "fixes" make the issue worse — recognise them so you don't ship them:

• Putting the filename into alt ("IMG_1234.jpg" tells nobody anything).
• Stuffing the alt with keywords that don't describe the image.
• Using the same alt across every product image on a category page.

Example

Here's a typical instance — the problematic line is highlighted in red:

<img src="/img/example.jpg" alt="A very long, keyword-stuffed alt description that exceeds 125 characters and reads as spammy to assistive technology…" />

And the fix — the corrected line, highlighted in green:

<img src="/img/example.jpg" alt="Concise descriptive alt under 125 chars" />

How atlookup detects this

Our crawler renders each page with a real headless browser, then inspects every <img> and <input type="image"> for the relevant attribute and length thresholds. Pages where the rule fires for image alt text too long are flagged on the report.

If you'd like to see this rule fire on your own site, run a free 60-second audit — every page is reported with the exact lines that triggered it.

Tools to verify the fix

Once you've applied the fix, double-check with these external validators:

• Lighthouse — Audit images for missing alt, lazy-load, and modern formats.
• axe DevTools — WCAG-aligned image accessibility check.
• WAVE — Visual overlay of every alt-related issue per page.

Frequently asked questions

Related issues