<h1>–<h6>: The HTML Section Heading elements - HTML: HyperText Markup Language 编辑
The HTML <h1>
–<h6>
elements represent six levels of section headings. <h1>
is the highest section level and <h6>
is the lowest.
The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.
The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.Content categories | Flow content, heading content, palpable content. |
---|---|
Permitted content | Phrasing content. |
Tag omission | None, both the starting and ending tag are mandatory. |
Permitted parents | Any element that accepts flow content; don't use a heading element as a child of the <hgroup> element — it is now deprecated. |
Implicit ARIA role | heading |
Permitted ARIA roles | tab , presentation or none |
DOM interface | HTMLHeadingElement |
Attributes
These elements only include the global attributes.
The align
attribute is obsolete; don't use it.
Usage notes
- Heading information can be used by user agents to construct a table of contents for a document automatically.
- Avoid using heading elements to resize text. Instead, use the CSS
font-size
property. - Avoid skipping heading levels: always start from
<h1>
, followed by<h2>
and so on. - Use only one
<h1>
per page or view. It should concisely describe the overall purpose of the content. - Using more than one
<h1>
will not result in an error, but is not considered a best practice. It is beneficial for screenreader users, and SEO. - While HTML5 allows a
<h1>
per sectioning element, it is not considered best practice, and may subvert the expectations of how screen reader users navigate.
Examples
All headings
The following code shows all the heading levels, in use.
<h1>Heading level 1</h1>
<h2>Heading level 2</h2>
<h3>Heading level 3</h3>
<h4>Heading level 4</h4>
<h5>Heading level 5</h5>
<h6>Heading level 6</h6>
Here is the result of this code:
Example page
The following code shows a few headings with some content under them.
<h1>Heading elements</h1>
<h2>Summary</h2>
<p>Some text here...</p>
<h2>Examples</h2>
<h3>Example 1</h3>
<p>Some text here...</p>
<h3>Example 2</h3>
<p>Some text here...</p>
<h2>See also</h2>
<p>Some text here...</p>
Here is the result of this code:
Accessibility concerns
Navigation
A common navigation technique for users of screen reading software is jumping from heading to heading to quickly determine the content of the page. Because of this, it is important to not skip one or more heading levels. Doing so may create confusion, as the person navigating this way may be left wondering where the missing heading is.
Don't
<h1>Heading level 1</h1>
<h3>Heading level 3</h3>
<h4>Heading level 4</h4>
Do
<h1>Heading level 1</h1>
<h2>Heading level 2</h2>
<h3>Heading level 3</h3>
Nesting
Headings may be nested as subsections to reflect the organization of the content of the page. Most screen readers can also generate an ordered list of all the headings on a page, which can help a person quickly determine the hierarchy of the content:
h1
Beetlesh2
Etymologyh2
Distribution and Diversityh2
Evolutionh3
Late Paleozoich3
Jurassich3
Cretaceoush3
Cenozoic
h2
External Morphologyh3
Headh4
Mouthparts
h3
Thoraxh4
Prothoraxh4
Pterothorax
h3
Legsh3
Wingsh3
Abdomen
When headings are nested, heading levels may be "skipped" when closing a subsection.
- Headings • Page Structure • WAI Web Accessibility Tutorials
- MDN Understanding WCAG, Guideline 1.3 explanations
- Understanding Success Criterion 1.3.1 | W3C Understanding WCAG 2.0
- MDN Understanding WCAG, Guideline 2.4 explanations
- Understanding Success Criterion 2.4.1 | W3C Understanding WCAG 2.0
- Understanding Success Criterion 2.4.6 | W3C Understanding WCAG 2.0
- Understanding Success Criterion 2.4.10 | W3C Understanding WCAG 2.0
Labeling section content
Another common navigation technique for users of screen reading software is to generate a list of sectioning content and use it to determine the page's layout.
Sectioning content can be labeled using a combination of the aria-labelledby
and id
attributes, with the label concisely describing the purpose of the section. This technique is useful for situations where there is more than one sectioning element on the same page.
Example
<header>
<nav aria-labelledby="primary-navigation">
<h2 id="primary-navigation">Primary navigation</h2>
<!-- navigation items -->
</nav>
</header>
<!-- page content -->
<footer>
<nav aria-labelledby="footer-navigation">
<h2 id="footer-navigation">Footer navigation</h2>
<!-- navigation items -->
</nav>
</footer>
In this example, screen reading technology would announce that there are two <nav>
sections, one called "Primary navigation" and one called "Footer navigation". If labels were not provided, the person using screen reading software may have to investigate each nav
element's contents to determine their purpose.
- Using the aria-labelledby attribute
- Labeling Regions • Page Structure • W3C WAI Web Accessibility Tutorials
Specifications
Browser compatibility
BCD tables only load in the browser
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.See also
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