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Table of Contents
What exactly should the main tag cover?
Use main to improve accessibility
The difference and coordination between main and other semantic tags
Home Web Front-end H5 Tutorial Identifying Main Content Using the HTML5 Main Element

Identifying Main Content Using the HTML5 Main Element

Jul 09, 2025 am 01:20 AM

The main element is used to wrap the core part of the page that is directly related to the current content and does not contain duplicate content or auxiliary areas. 1. The main tag clearly identifies the main content area of ??the web page; 2. It improves barrier-free experience and allows screen readers to jump quickly; 3. Each page can only have one main element, which should be placed in the body and exist independently; 4. It is often used with semantic tags such as header, nav, footer, etc. to build a clear structure; 5. When using it, avoid nesting unrelated interactive components or content that affects the main line logic.

Identifying Main Content Using the HTML5 Main Element

Using the main element of HTML5 to identify the main content is actually a practical but often overlooked approach. Simply put, the main tag is used to clarify the "most core" content area in the page. It's not for layout, but for semantics and accessibility - allowing screen readers, search engines, and even browser plug-ins to more accurately determine which piece of content is what users are really looking at.

Identifying Main Content Using the HTML5 Main Element

What exactly should the main tag cover?

Many people will get confused at the beginning: Does main equal to the content area? Not exactly. Its function is to wrap the main content of the document or application, that is, the core part directly related to the current page.

Identifying Main Content Using the HTML5 Main Element

For example, in an article page, main should include the title and body, rather than the sidebar, footer, or navigation bar. Notice:

  • Don't put content that appears repeatedly on multiple pages into main (such as a universal sidebar or ad)
  • Each page can only have one main element
  • It is usually inside a body and does not need to be nested in a header or footer

That is, main is "unique" and "independent".

Identifying Main Content Using the HTML5 Main Element

Use main to improve accessibility

For users using screen readers, the main tag is like a fast lane. They can jump directly to the main area via shortcut keys without listening to the navigation menu from scratch every time.

This is actually one of the built-in accessibility features of HTML5. Compared to just relying on class names or divs to build structures, using main is like labeling "Please read me first" to important content.

If you want to optimize further:

  • Make sure that the content behind main does not affect the main line logic (such as pop-up windows or floating ads)
  • Avoid stuffing too many interactive components into main unless they are at the heart of the current task
  • Combining aria-labelledby or title attributes to enhance illustrativeness (although main itself already has an implicit role)

The difference and coordination between main and other semantic tags

Although main is good, it does not exist in isolation. It can only be used with other HTML5 semantic tags to bring about its value.

for example:

  • header and main can exist side by side, header places the title information of the page or block
  • nav is usually placed in header or aside, not in main
  • footer usually means the end of the page after main

A common structure is probably like this:

 <header>...</header>
<nav>...</nav>
<main>...</main>
<footer>...</footer>

But it should be noted that main does not have to be close to the header or footer, as long as the overall structure is clear.


Basically that's it. The main tag looks simple, but if used correctly, it can make the web page structure clearer and easier to access. Don’t underestimate this tag. It is not only a semantic optimization, but also a part of improving user experience in modern web development.

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