HTML Guide
An a
element with an href
attribute provides a link to a resource, so adding the link
role to it is redundant.
When not using semantic HTML for its intended purpose, interactive features must be re-implemented. For example, when role="link"
is added to an element, the tab
key should enable giving focus to the link and the enter
key should execute the link when focused.
Learn more:
Related W3C validator issues
The <a> element requires either a href attribute, or a role attribute.
A button element, or an element with the role=button attribute, is not allowed to be nested inside an <a> element.
The href attribute of an <a> element contains an invalid character, that should be properly encoded as a URI percent-encoded character.
An illegal character has been found for the “href” attribute on the “link” element.
To fix this issue, find the “link” element in question and make sure that the “href” attribute contains a valid URL without any illegal characters.
Here’s some example HTML code of a link element:
<!DOCTYPE html>
<html>
<head>
<title>My Webpage</title>
<link rel="stylesheet" href="styles/main.css">
</head>
<body>
<h1>Welcome to my webpage!</h1>
<p>Here is some content...</p>
</body>
</html>
In the above example, the link element has a valid href attribute value of styles/main.css. Make sure that your href attribute values don’t contain any illegal characters.
The href attribute on the link element must not be empty.
The href attribute on an a tag expects a valid URL, but only http(s):// was found.
<a> tags can be used to link to an email address using the mailto protocol in the href attribute. Ensure that there is no space in the email address.
<a href="mailto: liza@example.com">This is wrong as it contains an space</a>
<a href="mailto:liza@example.com">This is OK</a>
The W3C HTML Validator issue you encountered indicates that the URL provided in the href attribute of an anchor (<a>) element is not formatted correctly.
How to Fix the Issue
- Check the Protocol: For a valid URL, make sure that after https: there are two slashes (//).
- Update the URL: Correct the URL format to include the missing slash.
Example of Incorrect HTML
Here is an example of the code that would trigger the validation error:
<a href="https:/example.comf">Example</a>
Corrected HTML
Here’s how the corrected code should look:
<a href="https://example.com">Example</a>
Summary
Make sure that all URLs within href attributes are correctly formatted with both slashes following the protocol (https:// or http://).
Hash (#) characters can be used in an href attribute to link to a specific part of a document.
For example, if we have this page with several sections, each of them marked with an ID:
<h1>Frequently Asked Questions</h1>
<h2 id="pricing">Pricing</h2>
<p>All about pricing...</p>
<h2 id="terms">Terms</h2>
<p>You can find our terms at...</p>
<h2 id="guarantee">Guarantee</h2>
<p>We offer a guarantee...</p>
You can link to a specific part of that document, for example if this page URL is /faqs and you want to link to the Guarantee section you could use:
<a href="/faqs#guarantee">Guarantee</a>
Or, if you’re linking from inside the same document, for example in a table of contents, you could just use:
<a href="#guarantee">Guarantee</a>
As there can only be one fragment in an URL, the # character should only be used once. The following would be an invalid href:
<a href="/faqs#guarantee#pricing">Bad</a>
If needed, the # could be encoded as %23.
Space characters are not allowed in href attributes. Instead, they should be converted to %20. In this example, the first line is invalid and the second is valid:
<a href="https://example.com#some term">invalid</a>
<a href="https://example.com#some%20term">valid</a>