Image Alt Text Checker

How it works

What we check

• Total images on the page — Counts every <img> element in the HTML, including content images, logos, and decorative graphics, so you know the full scope of what needs alt text.
• Images with alt text — Counts the <img> elements that have a non-empty alt attribute. Note that an intentionally empty alt="" (used to hide purely decorative images from screen readers) is a valid, deliberate choice — different from simply omitting the attribute.
• Images missing alt text — Flags every image with no alt attribute at all, or an alt attribute that is blank/whitespace where descriptive text was expected. These are the images that fail both image SEO and WCAG.
• Alt coverage score — A percentage: images with alt text divided by total images. A page with no images at all scores 100 (nothing to fix). Aim for full coverage on all meaningful content images.
• Source URLs of missing images — Lists the src (or data-src for lazy-loaded images) of each image missing alt text — the first 40 — so you can locate and fix the exact files rather than hunting through the page.
• Lazy-loaded image sources — Reads data-src when an image uses lazy loading and src is a placeholder, so lazy-loaded images aren't wrongly reported as having no source.

Common issues we catch

• Missing alt attribute entirely — An <img> with no alt attribute gives search engines nothing to index for image search and forces screen readers to announce the file name (or just 'image'). Every meaningful image needs descriptive alt text. This is the single most common finding.
• File name dumped into alt text — Alt text like 'IMG_4821.jpg' or 'DSC00031' is technically present but useless — it describes nothing. It passes a naive 'has alt' check but fails users and SEO. Replace it with a plain-language description of what the image shows.
• Keyword-stuffed alt text — Cramming alt text with repeated keywords ('running shoes best running shoes cheap running shoes') reads as spam to search engines and is jarring to screen-reader users. Describe the image naturally; if a keyword fits, fine, but write for a person first.
• Decorative images that should be empty, not described — Purely decorative images (spacers, background flourishes) should use alt="" so screen readers skip them. Giving them verbose alt text adds noise for users navigating by audio. Knowing which images are content vs. decoration is the judgment call this surfaces.
• CSS background images can't have alt text — Images set via CSS background-image aren't <img> elements and can't carry alt text at all. If a background image conveys meaning (like an infographic), it's invisible to search and screen readers — it should be a real <img> with alt instead.
• Lazy-loaded or JavaScript-injected images — Images added by lazy-loading scripts or client-side rendering may carry the real source and alt in data attributes or appear only after load. They can look fine on screen but be missing or alt-less in the initial HTML a crawler reads.
• Alt text duplicated across many images — Galleries that auto-fill every image with the same alt (e.g. the page title) provide no per-image meaning. Each distinct image should have alt that describes that specific image, not a generic shared label.

Where this matters

• Google Images — Alt text is a primary signal Google uses to understand and rank images in image search. Descriptive, accurate alt text is how a photo on your page earns traffic from people searching for that subject.
• Screen readers (JAWS, NVDA, VoiceOver) — Blind and low-vision users hear the alt text read aloud in place of the image. Missing alt means they hear a file name or nothing; good alt means they get the same information sighted users do.
• WCAG 2.1 (Success Criterion 1.1.1) — The 'Non-text Content' criterion requires a text alternative for images that serve a purpose. Missing alt text is one of the most common WCAG failures flagged in accessibility audits and ADA-related reviews.
• WordPress, Shopify & Wix — Every media library lets you set alt text per image, but it's optional and frequently skipped on upload. Themes and product imports often leave it blank entirely — exactly the gap this tool finds across a page.
• Social & link previews — While share previews use Open Graph images, accessible alt text on in-page images still benefits users on assistive tech across every browser and improves the overall quality signals of the page.