Image alt text checker
Enter a page and this tool lists every <img> in its HTML next to its alt text. It separates images with no alt attribute, which screen readers handle badly, from those with an empty alt, the correct way to mark decorative images.
It’s for makers who want their pages usable with a screen reader and readable by image search. Alt text is one of the simplest accessibility fixes, and pages often have far more images than people remember.
Free with a ShipScroll account.
How to use the Image Alt Text Checker
- Enter the page to scan.
- Press Check images.
- Add alt text to every image listed as missing it, describing what the image shows.
- Look at the ones with empty alt and make sure they really are decorative.
Missing alt versus empty alt
| Markup | What a screen reader does | When it’s right |
|---|---|---|
| <img src="x.png"> | May read out the file name | Never |
| <img src="x.png" alt=""> | Skips the image | Decorative images, spacers, icons beside text that says the same |
| <img src="x.png" alt="Dashboard showing weekly sign-ups"> | Reads the description | Any image that carries meaning |
Writing useful alt text
- Describe what the image shows and why it’s there, in a short sentence.
- Don’t start with “image of”: screen readers already say it’s an image.
- If the image is a link or button, describe where it goes or what it does.
- For a chart, give the main point, and put the detail in the page text.
- Use your keywords only where they describe the image honestly.
What this checker can’t see
It counts <img> tags in the HTML your server sends. CSS background images, inline SVGs and images added later by JavaScript aren’t included. It also can’t judge whether alt text is accurate, only whether it’s there.
Questions
Does alt text help SEO?
Google says it uses alt text, along with the page around an image, to understand what the image is about. That helps in image search. The bigger win is for people using screen readers.
Should every image have alt text?
Every image should have an alt attribute. Images that carry meaning get a description, and purely decorative ones get an empty alt="".
How long should alt text be?
There’s no hard limit, but a short sentence is usually right. The tool flags alt text over 150 characters, because long descriptions are tiring to listen to. Put detail in the page instead.
Why are only some images listed?
We list the first 200 images. The counts at the top always cover every image in the HTML.
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