What is an H3 tag?

An H3 tag is an HTML element that is used to specify subheadings under an H2 heading.
Where the H1 forms the main structure and the H2 marks the most important subheadings, the H3 tag helps to further divide the content into organized sections.

In HTML, it looks like this:

<h3>Jouw subkop</h3>

The H3 tag is ideal for better structuring texts, both for visitors and search engines.
It provides a clear hierarchy: H1 > H2 > H3. This way, Google understands exactly how your content is structured and which topics belong together.

Why are H3 tags important?

H3 tags make it possible to present complex content clearly.
They break long sections into manageable pieces of text and thus improve the reading experience.

In addition, H3 tags help search engines make deeper connections between topics.
A well-structured hierarchy of H2s and H3s shows that your content is carefully structured — something Google loves.

In short: H3 tags ensure that your content performs better organically and becomes more user-friendly.

H3 tags in practice

Let's say you're writing an article about SEO optimization.
Your H1 could then be:

<h1>SEO optimization: the complete guide</h1>

Your H2s divide the subject into logical blocks, such as:

<h2>Technical SEO</h2>
<h2>Content optimization</h2>
<h2>Link building</h2>

Under those H2s, you then use H3 tags to further delve:

<h3>Optimizing Meta Tags</h3>
<h3>Improving internal link structure</h3>
<h3>Increase page speed</h3>

This is how you make your article logical, structured and SEO-technically strong.

H3 tags and SEO

The H3 tag, like the H1 and H2, affects on-page SEO.
Google reads H3s to understand context and make connections between main topics and subtopics.

In addition, H3 tags are a good place to process long-tail keywords.
These search terms often have less competition, making it easier to rank on multiple variations within the same article.

For example:

• H2: Content Optimization
• H3: Content optimization for web shops
• H3: Content Optimization for Local Businesses

This way, you can include multiple related searches in one article.

How often can you use an H3 tag?

There is no hard limit.
Use as many H3s as necessary to divide the text logically. Guidance: 2 to 4 H3 tags per H2 section is usually ideal.

The most important thing is consistency.
Only use an H3 as a subheading under an H2, not randomly interchangeably. This way, your hierarchy remains clean and understandable to search engines.

H3 tags in WordPress

In WordPress, you can easily add an H3 tag via the header settings in the editor.
Select a subheading and choose “Heading 3” from the drop-down menu.
Optionally, use an SEO plugin (such as Rank Math or Yoast) to check that your heading structure is correct and does not break through levels (e.g. H4 directly below H2 with no H3 in between).

Rank Rocket tip

Use H3 tags strategically.
Where the H2 introduces the subject, you can go in-depth with H3s: explanations, examples, roadmaps or practical tips.

Pages with a well-structured H3 structure often generate longer reading time, lower bounce rate, and more featured snippets because Google understands the structure better.

My advice

Use H3 tags to reinforce your H2 sections.
Make sure they are logical, informative and, of course, readable. Avoid keyword stuffing, focus on relevance and clarity.

With each H3, think about the question you're answering. If the reader expects more depth after your H2, that includes an H3.

A strong headline structure (H1, H2, H3) is not only great for SEO, but also for conversion: readers stick around longer, scan faster, and trust your content more.