There are many debates over the usefulness of categories and tags for SEO Perth. A lot has been said about both but most information sources are inconsistent or incomplete. So how many tags can I use? How many categories should I have? How are tags better for SEO than categories, or the other way round? If you have these questions, reading this will help you improve your own blog.

What are tags and categories?

Tags and categories are filters that allow you to sort content. For example, you may wish to group information by topic or alphabetically. They allow others to navigate your site easily.

What’s the difference between tags and categories?

Categories are more general than tags and usually group together broad topics. In categories you also have sub-categories. Sub-categories narrow topics even more and help users find more specific information. Categories also give others an understanding of what your blog is about.

Tags are used to describe blog posts. They tell users what’s in a post, and can be thought of as tiny categories. Unlike categories, tags do not have sub-tags. This means the first tags in a post are not always most important and the last tags are not always least important.

An easy way to know the difference between categories and tags is to think of a clothing store. There are different categories like men’s, women’s, and children’s sections. Sub-categories could be shirts, pants or shoes. Tags could be different brands, prices or colours. You’ll find some brands in multiple departments. That’s the same for tags being used in multiple categories.

An important difference between categories and tags is that posts must be categorised. If not, posts will be automatically placed in the “Uncategorised” category. People often change its name to “other” instead. Tags are not required in posts and do not affect which category they are in.

How many WordPress categories should I have?

There is no best number of categories a website should have. The number of categories used is often based on the information your site has.Complex blogs with thousands of posts need more categories than one with hundreds. It is always wise to categorise so that others can easily navigate your site.

The best way to categorise is to start out broadly. Make sure main category names are ‘timeless’ so they don’t need to be changed in the future. What does this mean? A photographer may have a category called “Dogs” but in the future post about cats. Renaming the category would confuse previous site viewers. The issue could have been avoided if the category was called “Animals” or “Pets”.

Having a few main categories will let you sub-categorise. It may mean making lots of sub-categories but it gives more specific information to site visitors.

When should i add sub-categories?

When you post content in a main category you may find that posts are similar. If you find content grouping together, it can be sub-categorised. Sub-categories are not a must, but they allow greater navigation of your content by others.

Can I have a post in more than one category?

It is possible to have a post in more than one category to help viewers find information. This could be because of too few categories or sub-categories though. Finding or making the right category for posts should be the first thing to do.

If you are concerned about duplicate content penalties you can (noindex, follow) categories. This tells search engine bots to index those categories. Be careful not to index main category archives or content will be duplicated.

How many tags can I use?

There are no limits to the number of tags you can put in a post on WordPress. Having lots of tags is not always helpful though. The purpose of tags is to highlight information to users. Having too many will make posts less specific and look like spam. Make sure tags are relevant and link to other posts that add value.

Do tags work like meta keywords?

Tags will only work like meta keywords if you have a plugin installed. WordPress SEO by Yoast will allow you to count tag values in the meta keywords template.

What is better for SEO? Categories or tags?

Neither! Categories and tags are most effective when they are both used. Understanding how they work by themselves is a great first step. The trick is working out how to use categories and tags together to improve navigation of your site by users. Then you will reap the SEO benefits!

What’s the optimal number of WordPress categories?

Up until WordPress 2.5, there was no built-in support for tags. This led to very long category lists because people were using it to define micro-details. Tags were added to improve the usability of your site. Having that said, we believe there is no specific optimal number of categories. The optimal number varies based on the complexity of your site. However, for the sake of structure and usability, it is best that you utilize sub-categories and tags.

Categories are meant to encompass a group of posts. It is always best to start with generic categories and work your way down with subcategories as your site grow. After having run multiple blogs, we have learnt that blogs evolve. There is no way that you can come up with all the right categories. Chances are when starting out, you are only writing one post a day. Or maybe 3-5 posts a day. Having 30 top categories is pointless specially when some of them will only have one or two posts. You are better off with 5 generic categories that have fresh content rather than 30 top categories where majority are not updated.

Let’s take a look at an example. Say that we are starting a social media blog in 2012. We want to share how-to tutorials, news, tools, case studies etc. We can create top categories like Twitter, Facebook, Google+, LinkedIn etc. As sub categories of each, we can have tools, how-to’s, case studies, news etc. However that is a very short-term mindset, and we will run into issues in the future. What if one of the social media network dies and a new one enters the game? You will be required to add yet another top level category and more sub-categories.

A much better way of structuring this social media blog would be to have top categories that are future-proof. You can have your categories like How-To’s, News, Case Studies, Tools, etc. But how would people know that it is about twitter? Well your categories are not suppose to do the entire job. This is where tags come in. Let’s say you wrote a how-to post about twitter, simply add the tag twitter. In your design just add a section called Popular Topics and control that manually with links to popular tags like Twitter, Facebook, Google+ etc.

When do you add subcategories?

Let’s say that you do a case-study posts where sometimes you interviewed an expert for a specific case-study. Because there is no category called “expert interviews”, you will add that as a tag on that case-study post. If you find yourself doing a lot of interviews for case-studies and your expert interviews tag has 10+ posts in it and is consistently growing, then you should consider adding expert interviews as a sub-category of your main category “Case Studies”.

Yes, you will have to go back and edit your older posts. If your URL structure is /category/postname/, then you have make sure you are using the Redirection plugin. It automatically redirects your modified posts to their new URL, so you can keep all the search engine rankings.

Do I have to use sub-categories?

No of course not. You can always leave popular tags as tags. In our example above, almost all posts will have a tag for a specific social media network like twitter, Facebook, etc. But we are not creating those as categories. The only reason why you add sub-categories is to make it easy for your users to find the content. You are more than welcome to simply add the Expert Interviews tag in your site somewhere.
Remember the whole purpose of categories and tags are to make it easy for your users to browse your site.

Is it okay to assign one post to multiple categories?

You might read on other sites that assigning posts to multiple categories can hurt your SEO. Some say that you can get penalized with duplicate content because of that. We believe that statement is not entirely true. First of all, don’t get lost with SEO. Remember the purpose of sorting your content efficiently is to help users find it. By the nature of how top categories should be setup, you shouldn’t be able to classify one post into multiple top-level categories. For example, if your blog has three categories “Advertising, Marketing, and SEO”. Your posts often tend to fall into multiple categories. Perhaps you need an umbrella category for all three? Maybe they should all fall under Business? Or you can have one category called Advertising & Marketing. Then have SEO as a sub-category for those.

There is no SEO benefits to adding multiple categories. If you think it helps your users, then you are more than welcome to add one post into multiple categories. However, if you see this becoming a regular issue, then you should consider restructuring your categories. Maybe some of your categories need to be tags. Or maybe they should be subcategories of one major category. It is mainly about making the user experience better.

If you are super concerned about duplicate content penalty, then simply (noindex, follow) your category taxonomy using the WordPress SEO by Yoast plugin.

If you only want to (noindex, follow) specific categories, then you can do so by editing the category themselves. Yoast plugin has the setting to override the global settings.

Basically when you (noindex, follow) certain thing, it tells Google and other search engine bots to follow all post links in these categories, so all posts can be indexed. However do not index the main category archives to prevent duplicate content.

Short answer: WordPress allows you to add one post into as many categories as you like. Yes it is okay to assign one post into multiple categories as long as you think it helps your users. However, if you think of categories as Table of Contents for your blog where posts are chapters, then can you have one chapter in two separate sections? The answer to that question is NO.

Is there a limit of tags we can assign to each post?

Short answer to this question is NO. WordPress has NO limits on the number of tags you can assign to a specific post. You can add 1000+ tags if you like. However, the purpose of tags is to relate your posts together. Again think of tags as the index or your book. These are popular keywords that you can use to loosely relate your posts. This makes it easy for users to find your posts specially when they are using the WordPress search. It also helps if you are utilizing the tag archive for users. We say add no more than 10 tags to your posts unless you can justify it. For example: if you are running a movie review blog, you may add multiple tags: actor/actress names (this alone can be over 10). But chances are that you may review multiple movies that have Adam Sandler in it. But for other simpler scenarios, you should really limit the amount of tags you use. Otherwise, you may find yourself with over 10000+ tags with only 300 posts on the site.

Do tags work like meta keywords?

Often people mistake tags to be like meta keywords for your blogs. This is the main reason why they try to add as many tags as possible. Tags are NOT meta keywords for your blog. At least not by default. Popular plugins like WordPress SEO by Yoast allows you to use your tag values to be in the meta keywords template. But if you don’t have these plugins configured to do that, then your tags DO NOT work like meta keywords.

Categories vs Tags: What’s better for SEO?

The most asked question that we see being asked on this topic is: Are there any SEO advantage of using categories over tags or vice versa? The simple answer to this is NO. You should NOT look at this as categories or taxonomies. They are meant to work together. If you have read this post, then you should be able to understand the individual purpose of categories and tags as well as their combined purpose for your site’s usability.


Your site is about your users not search engine bots. The goal of every search engine is to think the way users think when valuing your content. If you make your decisions based on usability, you will almost always find yourself reaping the SEO benefits. Categories and Tags are just the two default taxonomies that comes with WordPress. Most advanced sites use custom taxonomies for sorting their content alongside with categories and tags. Think of your blog as an ever evolving book. Choose the Table of Content (categories) wisely. Make sure that they are broad topics, but be cautious to not make it too vague. Use tags to loosely relate multiple posts. If you see a certain tag is becoming popular, then consider adding it as a sub-category. However, if you have to add the tag as subcategory of multiple top-level categories, then leave it as a tag. The goal is always to make the site as user friendly as possible.
We hope that this article helps clear any and all confusion when it comes to the topic of categories vs tags. We would love to hear your thoughts on this matter. How do you sort your content? what best practices do you follow?

Alistair Hinchliffe

SEO Specialist