HTML Header tags, as their name suggests, are used to differentiate the headings and sub-headings of a page from the rest of the content. These tags are also known to webmasters as heading tags or simply header tags.
The most important heading tag is the h1 tag and least important is the h6 tag. In HTML coding, the heading tags from h1 to h6 form a top-down hierarchy. This means that if you skip any of the tag numbers the heading structure will be broken, which is not ideal for on-page SEO.
For example, if your site is introduced with an h1 tag followed by an h3 tag, the hierarchy will be broken, meaning the heading structure is not as SEO-friendly. This doesn't apply, however, to the bottom-up structure, which could jump from an h4 to an h2 without issue. Ideally, every page should have an h1 tag, but never more than one.
Do not stuff your heading tags with keywords.
Do not use more than one h1 tag on a page. Usually, pages will have a single h1 heading and including two might make search engines think this as an attempt to include more keywords for SEO in multiple h1 tags. It is better to divide the content into two separate topics on individual pages with their own h1 tags. This makes more sense to both readers and the search engine spiders, however, using multiple h1 tags is allowed.
Do not use heading tags as hidden text. Any hidden text can result in penalties for your site, especially if the hidden part is a component that affects SEO.
Do not repeat heading tags on different pages of your site. It is a good practice to have unique heading tags throughout your site. Avoid using identical content for both your page’s h1 tag and meta title tag.
Do not use heading tags for styling text but use them for presenting organized and structured content on pages. Use CSS stylesheets for the purpose of styling.
A note about HTML5: Pages using HTML5 can use h1 tags as section headers for content, which means they can have one h1 tag per section. A page can have multiple h1 tags using HTML5 like this:
<div> <header><h1>How to Do On Page SEO</h1> </header> <article> <h1>On Page Content</h1> <h2>HTML Headers</h2> <p>Body text<p> </article> <article> <h1>Technical SEO</h1> <h2>Meta Tags</h2> <p>Body text<p> </article> </div>