Images added by JavaScript with no alt: two weaknesses combined

In brief

Images added by JavaScript have no alt attribute: they combine two weaknesses, invisible in the raw HTML and without alternative text. Google Images will probably ignore them and screen readers cannot describe them. Add the alt attributes and render these images server-side if possible.

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What is it?

Images added by JavaScript have no alt attribute.

Why it hurts SEO and AI

Two weaknesses combined: images invisible in the raw HTML AND without a description. Google Images will probably ignore them; the accessibility impact is the same.

When it is NOT a problem

  • The images are purely decorative: an empty alt (alt="") is then correct and intentional.
  • Your important content images are already in the raw HTML with an alt: only secondary JS thumbnails are affected.
  • The page is an app interface not meant for image search.
Before
<!-- Image injected by JS, no description -->
<img src="/product.jpg">
After
<!-- Image in the raw HTML, with descriptive alt -->
<img src="/product.jpg" alt="Blue trail running shoe, side view">

The alt attribute serves both Google Images and screen reader users; rendering the image server-side also makes it discoverable.

How to fix it

  1. View the raw page source (Ctrl+U) and spot images absent from the source or without an alt attribute.
  2. Add a concise, descriptive alt to every meaningful image (empty alt for purely decorative images).
  3. Render content images server-side (SSR/SSG) instead of injecting them after load.
  4. Re-crawl to confirm the images appear in the raw HTML with their alt.

This scan checks what is missing from the raw HTML but appears in the JavaScript render

Is this issue on your site?

Are your images in the source code with an alt, or added after JavaScript? Enter a URL: Seogard compares the raw HTML and the render and shows you the images Google ignores. Free, no credit card.

By clicking Scan, I certify that I own this site or have permission to crawl it.

  • No credit card
  • Result in ~30 s

What you get back

Indexable, accessible images.

Seogard catches this regression automatically — through its SSR checker.

Frequently asked questions

What is the alt attribute on an image for?

It describes the image for Google Images and for the screen readers of visually impaired users. Without alt, the image is hard to index and inaccessible.

Do all images need an alt?

Meaningful images, yes. Purely decorative images should carry an empty alt (alt="") so screen readers skip them.

Related rules

Images without altSome images have no alt attribute. Important for accessibility and image SEO. Warning if 10+ images are affected. Title lengthThe meta title is too short (< 15 characters) or too long (> 60 characters). Google may truncate or rewrite it. Description lengthThe meta description is too short (< 50 characters) or too long (> 160 characters). Ideally between 120 and 155 characters.

Updated July 10, 2026