CometWeb tools
Alt text checker
Give a URL or paste HTML · alt attributes checked
A URL you enter is fetched by our server, so it reaches our logs. Code you paste by hand still never leaves your browser.
Paste a page source or just a fragment. Pasted code is analysed locally — nothing is uploaded.
Enter a URL or paste HTML
Every <img>, <area> and <input type="image"> is checked. Pasted code is not uploaded.
This alt text checker reviews the page at a URL you enter, or HTML you paste: missing alt attributes, a filename used as the description, a redundant "image of" prefix, a linked image with no accessible name, and alt text longer than useful. It judges presence and known anti-patterns — it cannot judge whether a description is apt, because that needs the picture.
When alt text actually fails
A missing attribute is not an empty one. alt="" says "this image adds nothing, skip it" and is correct for decoration. No alt at all makes a screen reader read the filename — which is how listeners get "D S C underscore zero zero four two dot j p g".
The worst case is a linked image with an empty alt and nothing else inside the link. The link then has no accessible name and is announced as a bare URL. WCAG 2.4.4 at Level A does not allow it.
"Image of" is wasted words. A screen reader announces the element role itself, so the prefix repeats what the user has already heard.
This checks presence and known anti-patterns. Whether a description is apt is decided by a person who can see the image and the sentence beside it — no automated check replaces that.
Read the image in context
Paste HTML that includes the image, its surrounding link and nearby text. Then view the page and decide what information the image contributes. The same image may need a description in an article and an empty alt in a decorative header.
W3C WAI · Easy Checks ↗Four cases
- ØNo alt
- A screen reader reads the filename. A WCAG 1.1.1 Level A failure.
- ""Empty alt
- Correct for decorative graphics — the image is skipped in the reading order.
- A→Linked image
- An empty alt with no other link content leaves the link unnamed. WCAG 2.4.4, Level A.
- 125Length
- Past roughly 125 characters a description stops being a label and becomes a paragraph to listen to.
Enter the page address and choose Fetch page. We download its HTML and check every <img>, <area> and <input type="image">: whether the alt attribute exists, whether it is a filename, whether a linked image has an accessible name, and whether the description runs long. For a page behind a login or a draft, paste its source or just the fragment with the images instead — pasted code is analysed locally in your browser.
No. alt="" is the correct and recommended markup for decorative graphics — it tells assistive technology to skip the image. It becomes a problem only on an image that carries meaning, or on the only element inside a link.
The specification sets no limit, but past roughly 125 characters a description stops being a label and becomes a paragraph to listen to. If an image needs a longer explanation, put it in the page content beside it.
No. It checks attribute presence and known anti-patterns in the markup it reads. It cannot tell whether a description conveys what the image means, and it does not cover the rest of WCAG — that needs a human review.
No statute names alt text as such. Accessibility law points at WCAG instead — the European Accessibility Act, Section 508 and their equivalents — and WCAG 1.1.1 is a Level A success criterion requiring a text alternative for non-text content. The obligation is real but indirect, and which law reaches you depends on where you operate and what you sell. This tool reads markup, not your legal exposure.
Right-click the image, choose Inspect, and read the alt attribute on the <img> tag. For one image that is faster than any tool and needs nothing installed. This checker is for the other case — a whole page at once, with the real problems separated from the images that are correctly marked decorative.
No. Analysis runs in your browser and the pasted markup never reaches CometWeb. A URL is different: our server fetches the page for you, so the address itself reaches our logs.
What else might come in handy
Automated WCAG 2.2 tests with a fix list and an action plan.