With the wealth of different blog options and settings, it can be confusing to determine the differences between blog tags and categories. However, it is important to understand these vital taxonomy elements. Simply put- categories are used to organize posts broadly whereas tags are often used to impart posts with specific meaning.

We will discuss other considerations for both categories and tags further in this article.

Blog Categories

Categories classify blog posts in general and broad terms and should be used sparingly to separate the main thematic elements of a blog. To illustrate, let's look at the categories of some of the top blogs:

  • Huffington Post, which is considered one of the most popular blogs, has the following major categories: News: Politics: Entertainment: Life: Personal, and Voices.
  • Mashable, another wildly popular blog, is even more concise with its categories. This site's major categories are  AI@Work: Tech: Science: Life: Social Good: and Entertainment.

Both of these major blog sites have these categories listed prominently on the banner of each site. These major categories are treated as sections of the site.  If you scroll down and click on a link on Engadget's site, the categories are available via a prominent dropdown labeled section at the top of the page for example.

In these examples, each top-level category is essentially a distinct sub-site. Additionally, categories can have hierarchical subcategories to further organize the structure of your blog site.

Hierarchical Categories

A parent category can have multiple hierarchical child subcategories. For example, if our parent category is Travel, we can have the various continents, Africa, America, Asia, Australia, Europe, and South America as sub-categories. Of course, each continent can have many child categories of their own.

Like the parent category, in most cases, each sub-category should also be general and broad. Also, you should keep the organization simple and not nest the categories too deep. If you are writing a post about an epic road trip along Utah Highway 12,  something like travel: Roadtrip: Utah would work just fine. You want to keep things broad so that the categories don't compete with one another.

Category Breadcrumbs

If you're using categories, breadcrumbs should be used with breadcrumb-structured data which will help google and other search engines to better understand your blog structure. Additionally, each category landing page may be indexed by Google and all of the category's blog posts will create an additional blog backlink raising your domain authority SEO score.

How Categories Impact SEO

If the top-level categories are used sparingly, and you have breadcrumb-structured data in place, having categories should help the search engines to better understand your site and improve your SEO score. However, make sure that you have enough blog content for each category. If you only have a couple of posts for each category- the search engines may think that your content is too thin.

It is also important to only have one top-level category per post. Every new top-level category or tag creates a new blog page. If you have dozens of top-level categories, there will be dozens of new pages and the search engines will penalize you as the content will seem too thin. Also, too many top-level categories will compete with each other and the search engine may think that you have duplicated your content.

Blog Tags

Unlike categories, tags are not hierarchical and are used to assign posts with a specific meaning. Tags act like a keyword and there can be many tags for a single blog post.

Popular social media sites, such as Twitter (now X) use hashtags for the same purpose. In my own Utah Highway 12 blog post, I have 4 different tags relating to the national parks along the road: Road Trip, Capitol Reef National Park, Bryce Canyon National Park, and Escalante National Monument. Readers who are interested in one of these national parks can click on the tag to find other related posts.

Tags Can Hurt SEO

Because there can be so many different tags for a given post, you can have a huge SEO penalty if the tags are not implemented correctly.

Like categories, each new tag will create a new blog page, and these new blog pages may only have just a few blog posts. If search engines are allowed to crawl your tags, your content will appear to be duplicated and seem quite thin. To prevent this, use no-follow links ("rel="nofollow") and block search engine indexing with noindex meta tags.

Using Tags in Conjunction With Categories

If you can block search indexing of your tags, you can use both tags and categories as long as you don't have too many of them. Try to keep the combined number of tags and categories under 12. However, you need to be careful when using tags. If you can't block tag search indexing, or are not sure how to use tags properly, you should not use them as they can be quite detrimental to your SEO score

Further Reading