Enter any page URL and our alt tag checker finds every <img> tag and reports which ones are missing an alt attribute — a quick accessibility and SEO win.
What is an alt tag checker?
An alt tag checker (or image alt tags checker) is a free tool that loads any web page, finds every image, and reports which ones lack a meaningful alt attribute. It's an alt attribute checker that works online — paste a URL to check image alt tags in seconds.
Check a website for missing alt tags
Missing alt text is one of the most common accessibility and SEO issues. This alt tag missing checker lists every image with a missing or empty alt so you can check missing alt tags across a page — the fastest way to check a website for missing alt tags before you publish.
Why image alt tags matter
The alt attribute describes an image to screen-reader users and to search engines. Good alt text improves web accessibility (WCAG), helps your images rank in Google Images, and adds keyword-relevant context to the page. An alt tag check should be part of every on-page audit.
How to use the alt tag checker
Paste a page URL into the image alt tag checker above.
Click “Check” — we fetch the live page and scan every image.
Review the list of images missing (or with empty) alt attributes.
Add concise, descriptive alt text to each image that needs it.
How to write good alt text
Keep it concise and descriptive (usually under ~125 characters), include a relevant keyword only when natural, and leave alt="" for purely decorative images. Pair this tool with our Title Tag Checker, Meta Description Checker, and the full free SEO tools suite.
Frequently asked questions
An alt tag checker is a free tool that fetches any page, finds every <img> element, and reports which ones are missing a meaningful alt attribute. It's also called an image alt tags checker or alt attribute checker, and it works online with no signup.
Paste the page URL into the alt tag checker above and run it. We fetch the live page, scan all images, and list every image with a missing or empty alt attribute — so you can quickly check a website for missing alt tags.
The alt attribute is text that describes an image. Screen readers read it aloud for visually impaired users, and search engines use it to understand image content (and to rank in Google Images). Missing alt tags hurt both accessibility and SEO.
A missing alt means the attribute isn't present at all (alt should be added). An empty alt (alt="") is valid for purely decorative images, telling screen readers to skip them. This alt tag missing checker distinguishes both so you know which images genuinely need descriptions.
Describe the image concisely and accurately in plain language (usually under ~125 characters). Include a relevant keyword only when it fits naturally. Leave alt empty for decorative images. Avoid “image of…” — screen readers already announce it's an image.
Completely free and online, with no account required. It's part of WebsiteAuditTools' free suite of on-page SEO and accessibility checkers.