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.
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Related W3C validator issues
The <a> element requires either a href attribute, or a role attribute.
A link element is invalid unless it contains at least one of the href or imagesrcset attributes.
The link element is used to define relationships between the current document and external resources, most commonly stylesheets. According to the HTML standard, a link must have either an href attribute, which points to the resource, or an imagesrcset attribute for responsive icons. If both are missing, the validator throws an error. This ensures that the link actually references a resource, otherwise it serves no functional purpose.
Correct usage:
With an href (for stylesheets, icons, etc.)
<link rel="stylesheet" href="styles.css">With imagesrcset (for responsive icons)
<link rel="preload" as="image" type="image/png" imagesrcset="icon-1x.png 1x, icon-2x.png 2x">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.
The href attribute of the a element contains an invalid backslash character, which is not permitted in URLs.
According to the WHATWG HTML living standard, the href attribute must contain a valid URL. URLs use forward slashes (/) for path separators, and backslashes are not allowed as they can cause browsers and validators to misinterpret the address. Backslashes often arise when file paths are copied from Windows environments.
Correct Usage:
- Always use forward slashes / in your URLs.
- Remove any backslashes from href values.
Example of incorrect usage:
<a href="images\picture.jpg">View Picture</a>Corrected example:
<a href="images/picture.jpg">View Picture</a>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://).