HTML Checking for Large Sites
Rocket Validator automatically checks your pages on the W3C Validator.
Stray start tag “head”.
A <head>
start tag has been found in an unexpected place in the document structure. Check that the <head>
section appears before the <body>
section, and that is not duplicated.
The <head>
section of an HTML document is the container of metadata about the document, and must appear before the <body>
section. A common cause of this issue is duplicated <head>
sections.
Here is an example of a minimal HTML document structure:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
</head>
<body>
<p></p>
</body>
</html>
Related W3C validator issues
The <head>
section of an HTML document contains metadata about the document, and as a minimum it must include a <title>
tag defining the document title.
Common causes for this issue are forgetting to define the <title>
, or duplicated <head>
sections where one of them does not include the title.
Here’s an example of a minimal HTML document including the title:
<!DOCTYPE html>
<html>
<head>
<title>Don't panic! This is the title</title>
</head>
<body>
<p></p>
</body>
</html>
And end tag has been found that does not match the current open element. Check the context to fix the start and end tags.
<meta>
tags, used for defining metadata about HTML documents, must appear within the <head>...</head>
section, but it has been found out of place. Check the document structure to ensure there are no <meta>
tags outside the head section.
A common cause of this issue is having a duplicated, out of place <head>...</head>
section. Ensure that this section appears in its proper place and is the only container for <meta>
tags.
An <a>
tag can’t include other <a>
tags inside. Most probable cause is an unclosed <a>
tag, like in this example:
<a href="one.html">Page 1
<a href="two.html">Page 2</a>
HTML documents are expected to start with a first line containing the Document Type Declaration, that defines the HTML version used. Since HTML5, it’s just <!DOCTYPE html>
, which must appear before the start <html>
tag.
Here’s an example of a minimal HTML5 document:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
</head>
<body>
<p></p>
</body>
</html>
All HTML documents must start with a <!DOCTYPE>
(Document Type Declaration), that informs browsers about the type and version of HTML used to build the document. In HTML5, this is simply <!DOCTYPE html>
and must appear at the start of the document.
Here is an example of a minimal HTML document, including the Document Type Declaration at its start:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
</head>
<body>
<p></p>
</body>
</html>
An end tag for X has been found that does not correspond to a previous open tag. This usually happens when you close the same tag twice, for example:
<ul>
<li>item</li>
</ul>
</ul>
A stray start tag <html>
has been found in the document. As this tag defines the start of the whole HTML document, it should appear only once.
A <script>
start tag has been found in an unexpected place in the document structure. Check that the <script>
section appears within the <head>
or <body>
sections.
Here’s an example of a script inserted in the head of the document:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
<script>
console.log("Hello from the head");
</script>
</head>
<body>
<p></p>
</body>
</html>
Learn more:
A <style>
start tag has been found in an unexpected place in the document structure. Check that the <style>
section appears within the <head>
section.
Although in general it’s better to put your styles in external stylesheets and apply them using <link>
elements, CSS styles can also be included inside a document using the <style>
tag. In this case, it should be placed within the <head>
section, like in this example:
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
<style>
p {
color: #26b72b;
}
</style>
</head>
<body>
<p>This text will be green.</p>
</body>
</html>
Learn more:
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