BYTETOOLS

Image Alt Text Checker

Paste HTML to list every image, image input and map area with its alt state, length, filename repeats, duplicates and how role or aria-hidden changes the verdict.

Decorative images should carry alt="" so screen readers skip them; meaningful images need a short description of what they convey in context. The whole check runs in your browser on the markup you paste.

What is the Image Alt Text Checker?

Paste a page's HTML and this checker parses it in your browser and lists every img element, every image input and every image-map area, with the state of its alt attribute: missing entirely, deliberately empty, or carrying a description.

  • Covers img elements, image submit inputs and image-map areas
  • Separates missing alt, deliberately empty decorative alt and real descriptions
  • Detects alt text that repeats the filename or duplicates another image
  • Flags redundant image-of openings and alt over 125 characters
  • Explains how role, aria-hidden and aria-label change the verdict
  • Copyable plain-text report — parsing happens entirely in your browser

How to use the Image Alt Text Checker

  1. 1

    Open your page, view source, and copy the HTML you want to check.

  2. 2

    Paste it into the box — a fragment works as well as a whole document.

  3. 3

    Read the counters for images found, missing alt, decorative and described.

  4. 4

    Work down the cards and fix anything marked red or amber.

  5. 5

    Copy the plain-text report to hand to a developer or attach to a ticket.

About the Image Alt Text Checker

Paste a page's HTML and this checker parses it in your browser and lists every img element, every image input and every image-map area, with the state of its alt attribute: missing entirely, deliberately empty, or carrying a description. Each one gets a plain-English verdict rather than a bare pass or fail.

It goes past the obvious missing-alt case. It flags alt text that just repeats the filename, alt text used identically on several images, alt longer than about 125 characters, redundant openings like 'image of', and the contradictions where an image carries alt text but is also marked aria-hidden or role=presentation.

This tool reads only the markup you paste — it never fetches a URL or crawls a site — and everything is analysed locally in your browser, so unpublished pages are safe to check.

Frequently asked questions

What is the difference between missing alt and empty alt?

A missing alt attribute is an error — screen readers fall back to announcing the filename. An empty alt is a deliberate instruction to skip the image, which is exactly right for decorative dividers, spacers and background flourishes.

How long should alt text be?

Aim for under about 125 characters. Most screen readers handle longer alt awkwardly, and anything that needs more explanation than a sentence belongs in a caption or the page text where every visitor can read it.

Should alt text start with 'image of'?

No. Screen readers already announce that the element is an image, so the phrase is repeated aloud. Start with the content instead — 'Red velvet sofa in a bay window' rather than 'Image of a red velvet sofa'.

Can this tool check a live URL?

No, and that is deliberate — it runs entirely in your browser with no network access. Copy the page source and paste it in, which also means you can check staging sites and pages behind a login.

Does alt text help SEO or only accessibility?

Both. Accessibility is the primary reason, but Google uses alt text to understand what an image shows, which is how images earn placement in Google Images and how they contribute context to the page they sit on.

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