How to Check Alt Text on Any Website (4 Ways)

The quickest way to check alt text on a website is to paste the page address into an alt text checker, which lists every image with its alt text and flags the ones where it is missing or empty. If you prefer to check by hand, your browser’s developer tools can do it too, and Lighthouse can flag missing alt attributes as part of an accessibility audit.

Here are four ways to do it, from fastest to most hands-on, plus how to check a whole site.

Way 1: Use a free alt text checker

1. Open the Alt Text Checker.
2. Paste the full address of the page, including https://, and click Analyze URL.
3. Read the results table. Each row is one image, with a thumbnail, its source, its alt text, its title attribute, whether it is linked, and a status.
4. Use the tabs to filter by Missing Alt Attribute, Empty Alt Text, With Alt Text, With Title Attribute or Linked Images.
5. Export the list as CSV if you need to share it.

The thumbnails make the review easier, because you can see the image and its alt text side by side and judge whether the text is any good.

Way 2: Inspect the page in your browser

You can look at the HTML directly:

• View the page source with Ctrl+U on Windows and Linux, or Option+Command+U on a Mac in Chrome. Search the source for <img and look at each tag for an alt attribute.
• Inspect a single image by right-clicking it and choosing Inspect. The Elements panel shows the live tag, including whether alt is there and what it says.

This is fine for one or two images, but slow for a whole page. Note that View Source shows the HTML the server sent, so images added later by JavaScript will not appear in it. Inspect shows the page as it is now.

Way 3: Run a snippet in the browser console

For a quick list of every image on the page as it currently stands, open developer tools (F12), go to the Console tab, and paste this:

console.table(
  [...document.images].map((img) => ({
    src: img.currentSrc || img.src,
    alt: img.getAttribute("alt"),
  }))
);

The document.images property returns every img element in the page. The table shows what each one’s alt attribute contains:

• null means the alt attribute is missing.
• An empty string ("") means the alt is present but empty, which is correct for decorative images.
• Anything else is the alt text itself.

To list only the images with no alt attribute at all, use:

[...document.images]
  .filter((img) => !img.hasAttribute("alt"))
  .map((img) => img.currentSrc || img.src);

Way 4: Run Lighthouse or WAVE

Lighthouse is built into Chrome’s developer tools. Open the Lighthouse panel, tick Accessibility, and run the audit. It reports image elements that do not have an alt attribute, along with many other accessibility issues, and shows which elements are affected.

WAVE is a free accessibility evaluation tool from WebAIM, available as a browser extension and on the web. It flags images with missing alt text and can show the alt text on the page itself.

Both are useful for a broader accessibility review. Keep in mind they check for the presence of the attribute. They cannot tell you whether the text is accurate or useful.

How to check alt text across a whole site

Checking page by page does not scale. To find images with missing or empty alt text across a site, crawl it with the Page Audit Checker. It lists every page it finds with a count of images that have empty alt text, so you can sort the CSV by that column and start with the worst pages. The count includes images whose alt attribute is missing and images where it is blank, so open the worst pages in the Alt Text Checker to see which images are the problem.

What to look for in the results

What you see	What it means	What to do
No alt attribute	A mistake: assistive technology has nothing to read, and some screen readers fall back to the file name	Add alt text, or alt="" if the image is decorative
Empty alt (alt="")	Deliberate for decorative images	Check it really is decorative, not a chart, product photo or button
File name as alt (IMG_2043.jpg)	Present, but useless	Rewrite it to describe the image
Same text on many images	Probably copied	Write a distinct description for each
A list of keywords	Keyword stuffing	Replace it with a plain description
”Image of…” at the start	Redundant	Remove the prefix

For what good alt text looks like, see How to Write Good Alt Text. If you are new to the topic, start with What Is Alt Text?.

What these checks cannot see

• Quality. Automated tools can find missing and empty alt text, but only a person can judge whether the text describes the image well in context.
• CSS background images. They are not img elements and have no alt text.
• Images loaded after the page is fetched. A checker that reads the server’s HTML, such as View Source or most online tools, may miss images added by JavaScript. The console snippet sees them once they are in the page.
• Images inside other documents, such as embedded frames, which need to be checked on their own page.

After you fix it

Update the alt text in your CMS or HTML, then run the same page through the checker again to confirm the problem is gone. If you are cleaning up images anyway, you can also make them smaller with the Image to AVIF Converter.

Frequently asked questions

Can I check alt text without a tool?

Yes. View the page source or inspect an image, or run the console snippet above. A checker is just faster and shows thumbnails.

How do I find images with no alt attribute?

Use the Missing Alt Attribute tab in the Alt Text Checker, or run the second console snippet. In Lighthouse, look for the audit about image elements that do not have an alt attribute.

Does View Source show every image on a page?

It shows the images in the HTML the server sent. Images that JavaScript adds afterwards will not be there, but they will appear in the Elements panel and in the console snippet.

Can a tool tell me whether my alt text is good?

Not reliably. Tools detect whether alt text is missing, empty or suspicious, such as a file name. Whether it conveys the right information for the page is a human decision.

How often should I check alt text?

Check after publishing new pages or changing templates, and run a site-wide crawl a few times a year. New images are where missing alt text usually creeps back in.