HTML Guide
The “Stray start tag “section”” error in the W3C HTML Validator typically occurs when a <section>
tag appears in an unexpected location within your HTML document structure. This can happen if the <section>
tag is not positioned correctly within the HTML5 content model.
Here’s a focused guide to fix this issue:
1. Check the Parent Element
Make sure the <section>
tag is placed within elements where it is allowed. According to the HTML5 specification:
-
A
<section>
element should be placed within the<body>
tag. - It should not be a direct child of an inline element or an element that does not support flow content.
2. Correct Nesting Within Elements
Ensure your HTML structure follows a logical hierarchy and that the <section>
element is not incorrectly nested. This example shows a correct usage of the <section>
tag:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Correct Usage of Section</title>
</head>
<body>
<header>
<h1>Page Title</h1>
</header>
<nav>
<!-- Navigation links -->
</nav>
<main>
<section>
<h2>Section Title</h2>
<p>Content for the first section.</p>
</section>
<section>
<h2>Another Section Title</h2>
<p>Content for the second section.</p>
</section>
</main>
<footer>
<p>Footer content</p>
</footer>
</body>
</html>
3. Check for Mistaken Hierarchy
Verify whether the <section>
tag is mistakenly placed inside elements that do not support it, such as directly inside a <p>
tag or other inline elements. Correct any incorrect usage. For example this is incorrect usage because the <section>
tag is placed after the closing <body>
tag:
Incorrect:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Sample page</title>
</head>
<body>
<h1>Main title</h1>
<p>Some content</p>
</body>
</html>
<section>
<h2>Incorrect Section</h2>
<p>This section should not be after the closing body tag.</p>
</section>
Correct:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Sample page</title>
</head>
<body>
<h1>Main title</h1>
<p>Some content</p>
<section>
<h2>Correct Section</h2>
<p>This section is fine.</p>
</section>
</body>
</html>
Summary
-
Ensure your
<section>
tags are used within the<body>
tag and other allowed elements. - Maintain a logical hierarchy in your HTML document.
-
Avoid placing
<section>
tags inside inline elements like<p>
.
Following these steps should resolve the “Stray start tag “section”” error in your HTML document. Validate your HTML again after making these corrections to ensure the issue is resolved.
Related W3C validator issues
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>
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>
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>
And end tag has been found that does not match the current open element. Check the context to fix the start and end tags.
The <section> element can be used to define sections of a document, like chapters, tabbed content, etc. Consider using a heading element (any of <h2> to </h6>) to present each section. Example:
<h1>All about guitars</h1>
<section>
<h2>Guitar types</h2>
<p>Acoustic, electric, classical... we have them all!</p>
</section>
<section>
<h2>Amplifiers</h2>
<p>Analog, digital, portable...</p>
</section>
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>
A <button> tag can’t include other <button> tags inside. Most probable cause is an unclosed <button> tag, like in this example:
<button>Submit
<button>Cancel</button>
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>