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: The HTML Section Heading Elements - MDN - Mozilla

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: The HTML Section Heading Elements - MDN - Mozilla

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  1. References
  2. HTML
  3. Elements
  4. <h1>
Article Actions
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    • 日本語
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    • Português (do Brasil)
    • Русский
    • 中文 (简体)
    • 正體中文 (繁體)
  • Try it
  • Attributes
  • Usage notes
  • Accessibility
  • Examples
  • Technical summary
  • Specifications
  • Browser compatibility
  • See also
  1. HTML
  2. Tutorials
  3. HTML basics
  4. Introduction to HTML
    1. Introduction to HTML overview
    2. Getting started with HTML
    3. What's in the head? Metadata in HTML
    4. HTML text fundamentals
    5. Creating hyperlinks
    6. Advanced text formatting
    7. Document and website structure
    8. Debugging HTML
    9. Assessment: Marking up a letter
    10. Assessment: Structuring a page of content
  5. Multimedia and embedding
    1. Multimedia and embedding overview
    2. Images in HTML
    3. Video and audio content
    4. From object to iframe — other embedding technologies
    5. Adding vector graphics to the web
    6. Responsive images
    7. Assessment: Mozilla splash page
  6. HTML tables
    1. HTML tables overview
    2. HTML table basics
    3. HTML table advanced features and accessibility
    4. Assessment: Structuring planet data
  7. References
  8. HTML elements
    1. <a>
    2. <abbr>
    3. <acronym> Deprecated
    4. <address>
    5. <area>
    6. <article>
    7. <aside>
    8. <audio>
    9. <b>
    10. <base>
    11. <bdi>
    12. <bdo>
    13. <big> Deprecated
    14. <blockquote>
    15. <body>
    16. <br>
    17. <button>
    18. <canvas>
    19. <caption>
    20. <center> Deprecated
    21. <cite>
    22. <code>
    23. <col>
    24. <colgroup>
    25. <data>
    26. <datalist>
    27. <dd>
    28. <del>
    29. <details>
    30. <dfn>
    31. <dialog>
    32. <dir> Deprecated
    33. <div>
    34. <dl>
    35. <dt>
    36. <em>
    37. <embed>
    38. <fencedframe> Experimental
    39. <fieldset>
    40. <figcaption>
    41. <figure>
    42. <font> Deprecated
    43. <footer>
    44. <form>
    45. <frame> Deprecated
    46. <frameset> Deprecated
    47. <h1>
    48. <head>
    49. <header>
    50. <hgroup>
    51. <hr>
    52. <html>
    53. <i>
    54. <iframe>
    55. <img>
    56. <input>
    57. <ins>
    58. <kbd>
    59. <label>
    60. <legend>
    61. <li>
    62. <link>
    63. <main>
    64. <map>
    65. <mark>
    66. <marquee> Deprecated
    67. <menu>
    68. <meta>
    69. <meter>
    70. <nav>
    71. <nobr> Deprecated
    72. <noembed> Deprecated
    73. <noframes> Deprecated
    74. <noscript>
    75. <object>
    76. <ol>
    77. <optgroup>
    78. <option>
    79. <output>
    80. <p>
    81. <param> Deprecated
    82. <picture>
    83. <plaintext> Deprecated
    84. <portal> Experimental
    85. <pre>
    86. <progress>
    87. <q>
    88. <rb> Deprecated
    89. <rp>
    90. <rt>
    91. <rtc> Deprecated
    92. <ruby>
    93. <s>
    94. <samp>
    95. <script>
    96. <search>
    97. <section>
    98. <select>
    99. <slot>
    100. <small>
    101. <source>
    102. <span>
    103. <strike> Deprecated
    104. <strong>
    105. <style>
    106. <sub>
    107. <summary>
    108. <sup>
    109. <table>
    110. <tbody>
    111. <td>
    112. <template>
    113. <textarea>
    114. <tfoot>
    115. <th>
    116. <thead>
    117. <time>
    118. <title>
    119. <tr>
    120. <track>
    121. <tt> Deprecated
    122. <u>
    123. <ul>
    124. <var>
    125. <video>
    126. <wbr>
    127. <xmp> Deprecated
  9. Global attributes
    1. accesskey
    2. anchor Experimental Non-standard
    3. autocapitalize
    4. autocorrect Experimental
    5. autofocus
    6. class
    7. contenteditable
    8. data-*
    9. dir
    10. draggable
    11. enterkeyhint
    12. exportparts
    13. hidden
    14. id
    15. inert
    16. inputmode
    17. is
    18. itemid
    19. itemprop
    20. itemref
    21. itemscope
    22. itemtype
    23. lang
    24. nonce
    25. part
    26. popover
    27. slot
    28. spellcheck
    29. style
    30. tabindex
    31. title
    32. translate
    33. virtualkeyboardpolicy Experimental
    34. writingsuggestions
  10. Attributes
    1. accept
    2. autocomplete
    3. capture
    4. crossorigin
    5. dirname
    6. disabled
    7. elementtiming
    8. for
    9. max
    10. maxlength
    11. min
    12. minlength
    13. multiple
    14. pattern
    15. placeholder
    16. readonly
    17. rel
    18. required
    19. size
    20. step
  11. <input> types
    1. <input type="button">
    2. <input type="checkbox">
    3. <input type="color">
    4. <input type="date">
    5. <input type="datetime-local">
    6. <input type="email">
    7. <input type="file">
    8. <input type="hidden">
    9. <input type="image">
    10. <input type="month">
    11. <input type="number">
    12. <input type="password">
    13. <input type="radio">
    14. <input type="range">
    15. <input type="reset">
    16. <input type="search">
    17. <input type="submit">
    18. <input type="tel">
    19. <input type="text">
    20. <input type="time">
    21. <input type="url">
    22. <input type="week">
  12. Guides
    1. Content categories
    2. Block-level elements
    3. Inline elements
    4. Quirks Mode and Standards Mode
    5. Date and time formats used in HTML
    6. Constraint validation
    7. Microdata
    8. Microformats
    9. Viewport meta tag
    10. Allowing cross-origin use of images and canvas
  • Try it
  • Attributes
  • Usage notes
  • Accessibility
  • Examples
  • Technical summary
  • Specifications
  • Browser compatibility
  • See also

The <h1> to <h6> HTML elements represent six levels of section headings. <h1> is the highest section level and <h6> is the lowest. By default, all heading elements create a block-level box in the layout, starting on a new line and taking up the full width available in their containing block.

Try it

Attributes

These elements only include the global attributes.

Usage notes

  • Heading information can be used by user agents to construct a table of contents for a document automatically.
  • Do not use heading elements to resize text. Instead, use the CSS font-size property.
  • Do not skip heading levels: always start from <h1>, followed by <h2> and so on.

Avoid using multiple <h1> elements on one page

While using multiple <h1> elements on one page is allowed by the HTML standard (as long as they are not nested), this is not considered a best practice. A page should generally have a single <h1> element that describes the content of the page (similar to the document's <title> element).

Note: Nesting multiple <h1> elements in nested sectioning elements was allowed in older versions of the HTML standard. However, this was never considered a best practice and is now non-conforming. Read more in There Is No Document Outline Algorithm.

Prefer using only one <h1> per page and nest headings without skipping levels.

Accessibility

A common navigation technique for users of screen reading software is to quickly jump from heading to heading in order to 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 do this:

html<h1>Heading level 1</h1> <h3>Heading level 3</h3> <h4>Heading level 4</h4>

Prefer this:

html<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 content hierarchy and navigate to different headings.

Given the following page structure:

html<h1>Beetles</h1> <h2>Etymology</h2> <h2>Distribution and Diversity</h2> <h2>Evolution</h2> <h3>Late Paleozoic</h3> <h3>Jurassic</h3> <h3>Cretaceous</h3> <h3>Cenozoic</h3> <h2>External Morphology</h2> <h3>Head</h3> <h4>Mouthparts</h4> <h3>Thorax</h3> <h4>Prothorax</h4> <h4>Pterothorax</h4> <h3>Legs</h3> <h3>Wings</h3> <h3>Abdomen</h3>

Screen readers would generate a list like this:

  1. h1 Beetles

    1. h2 Etymology

    2. h2 Distribution and Diversity

    3. h2 Evolution

      1. h3 Late Paleozoic
      2. h3 Jurassic
      3. h3 Cretaceous
      4. h3 Cenozoic

    4. h2 External Morphology

      1. h3 Head

        1. h4 Mouthparts

      2. h3 Thorax

        1. h4 Prothorax
        2. h4 Pterothorax

      3. h3 Legs

      4. h3 Wings

      5. h3 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.

Sectioning content examples

html<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

Examples

All headings

The following code shows all the heading levels, in use.

html<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>

Example page

The following code shows a few headings with some content under them.

html<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>

Technical summary

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.
Implicit ARIA role heading
Permitted ARIA roles tab, presentation or none
DOM interface HTMLHeadingElement

Specifications

Specification
HTML Standard # the-h1,-h2,-h3,-h4,-h5,-and-h6-elements

Browser compatibility

html.elements.h1

BCD tables only load in the browser

html.elements.h2

BCD tables only load in the browser

html.elements.h3

BCD tables only load in the browser

html.elements.h4

BCD tables only load in the browser

html.elements.h5

BCD tables only load in the browser

html.elements.h6

BCD tables only load in the browser

See also

  • <p>
  • <div>
  • <section>

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