Image Alt Text Checker

Find every image on a webpage missing alt text. Missing alt tags hurt your SEO rankings and fail accessibility standards fix them all in one go.

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Why alt text matters for SEO

Google can't see images — Googlebot reads alt text to understand what an image shows. Without alt text, your image contributes zero SEO value and won't rank in Google Images.

Empty alt vs. missing alt are different — An empty alt="" is intentional — it tells screen readers to skip the image (correct for decorative images). A missing alt attribute is an error — the image has no description at all.

Accessibility = SEO signal — Google's helpful content guidelines reward accessible pages. Pages that fail WCAG accessibility standards (including missing alt text) perform worse in rankings.

Image search is real traffic — Properly alt-tagged images appear in Google Image Search. For e-commerce, blogs, and recipe sites, Google Images can drive 20–30% of total organic traffic.

Frequently asked questions

What is image alt text?

Alt text (alternative text) is an HTML attribute that describes the content of an image. It's used by screen readers for accessibility and by search engines to understand image content.

Does alt text affect SEO rankings?

Yes. Alt text helps Google understand your images, which can improve rankings for both regular search and Google Image Search. Missing alt text is a missed ranking opportunity.

What makes good alt text?

Describe the image accurately in 5–15 words. Include your target keyword naturally if it's relevant to the image. Don't start with 'Image of' or 'Picture of' — that's redundant.

Should decorative images have alt text?

No. Decorative images (dividers, backgrounds, icons) should use empty alt="" to tell screen readers to skip them. Only meaningful, content images need descriptive alt text.

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SEOMentor scans every image on every page missing alt text, unoptimised sizes, missing WebP, and more.

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