When laying out a page, headings provide a semantic way to lay out sections of content. A heading element briefly describes the topic of the section it introduces. Heading elements are used by users of assistive technology to navigate a page quickly and to understand the structure of a page. Also see Landmarks.

When using heading elements, reserve the <h1> element for the page title. On the home page, this is usually the title of the site and on other pages, this may be the page title. Use the <h1> element once per page—some assistive technology may be unable to read multiple <h1>s on a single page correctly. Other heading levels may be used more than once following document outline order and you may reset headings up to <h2> with the <section> element.

For sub sections, use <h2> to <h6> in document outline order. <h2> is the most important and <h6> is the least. Avoid skipping headings. Avoid breaking document outline order (you may go from <h2> to <h3>, but never <h3> to <h2>).

For logos that are text-based, use <em> element.

If your logo is an image and acting as the main heading of the page, add an <h1> element for its text and use a sr-only rule so it’s visibly hidden but accessible to screen reader users.

Testing

1. Identify visual ‘heading’ elements
2. Check that all visual ‘heading’ elements use an <h> tag
3. Verify that all sub heading elements have a higher number

Examples

PASSES

Category

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 1

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 2

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 2

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 1

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 2

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 3

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

<h2>Category</h2>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h3>Sub Category, Level 1</h3>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h4>Sub Category, Level 2</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h4>Sub Category, Level 2</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h3>Sub Category, Level 1</h3>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h4>Sub Category, Level 2</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h5>Sub Category, Level 3</h5>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

This section has a main category, as well as level 1, 2, and 3 sub categories. Sub categories that are on the same level are using the the same heading elements. The level 3 sub category is nested correctly under the level 2 sub category and not vice-versa.

FAILS

Category

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 1

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 2

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

Sub Category, Level 3

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.

<h2>Category</h2>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h1>Sub Category, Level 1</h1>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h4>Sub Category, Level 2</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

<h6>Sub Category, Level 3</h6>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam sit amet auctor lectus. Curabitur non est nibh. Suspendisse vehicula fermentum quam. Donec lobortis diam a ligula faucibus mattis.</p>

This section has several issues. The first sub category has a lower h value than the main category. The second sub category has skipped a heading level which, while better, can cause confusion. It’s not clear if this category is the sub category of Category or Sub category, Level 1. The same problem is repeated with Sub Category, Level 3, as it should be an h5 when following an h4 heading.