How many keywords should I use for SEO? 

A common question beginner SEOs ask when optimizing an article is, “how many keywords should I use?” Is it better to focus on one keyword or multiple? And what about keyword variants and secondary keywords?

The answer to how many keywords you should use for SEO is exactly one. Yes, one keyword per page. Does this mean you should purposely avoid using other keywords on your page? Not quite.

See, when I say one keyword per page, what I really mean is it’s best to focus on a particular topic with clear search intent. This approach was a bit different from the early SEO days. Back then, Google wasn’t quite as smart. If you didn’t have the exact keyword that the user was searching for on your page, you may not have ranked so well. This led to SEOs pluralizing keywords and even purposely misspelling words to match keyword searches. This practice is called keyword stuffing and goes against Google’s spam policies.

Today, however, Google is much smarter. Back in 2019, Google announced that it would be using a machine learning AI called BERT (Bidirectional Encoder Representations from Transformers). With the help of BERT, Google can better understand what users are searching for and what pages are about. Google is able to deliver better search results.

In an online webinar, Google made a few points about BERT and exact keyword matches:

And with all of these… machine learning approaches, we try to figure out what these pages are actually about, what the query is actually looking for and we try to match that a little bit better.

From my point of view, all of these changes that have been happening over the years, they do lead in the direction that you don’t have to have the exact keywords on your pages anymore.

And this is something that I think SEOs have seen kind of maybe subconsciously over the years as well, where they realize oh you don’t need to have singular and plural versions on your page. You don’t need to have all of the common misspellings on your page.

All of those things are less critical on your pages as long as you really match what the user is actually looking for.

John Mueller, Senior Search Analyst at Google

So what does this all mean? Basically, Google has been moving away from exact keyword matches and more toward learning the search intent behind the keyword. This is because there can be many variants of a keyword but the search intent behind them is all the same.

For example, take the keyword, “how to change a tire”. We can find other keyword variants such as:

  • How to change a car tire
  • Steps to change a car tire
  • How to change a tire on a car
  • How to replace a tire

As you can see, these keyword phrases are unique in the way they are written, but they all have the same search intent. So, when I say to focus on a single keyword, what I really mean is to focus on a single search intent.

Okay, but which keyword should I use for my article?

Before you begin writing an article, you want to pick a primary keyword. A primary keyword is a keyword that represents the main topic of your page. This keyword is used in your URL, title, and headings. Sometimes, as we saw above, there may be different variants of primary keywords to choose from. In such cases, it’s best to pick the most common variant. For this, you can look at the keyword volume to help decide. In addition to your primary keyword, your article will often contain sub-topics that contain more detailed information. To represent these sub-topics, you can have secondary keywords.

  • Primary keyword: A single keyword to be used in your URL, title, and some headings.
  • Secondary keywords: Keywords that represent more detailed information. These are often used in sub-headings and inside content.

Both primary and secondary keywords may be used throughout your article, but it’s best to use them naturally in your writing.

So, should I still use exact keyword matches or not?

Using the exact keyword phrase in your content isn’t necessarily good or bad. I still believe exact keywords in your content can be beneficial when done correctly.

Here are some tips for using keywords in your content:

  • Use the keyword naturally
  • Don’t overuse the keyword so that it sounds repetitive

This means for some keywords, you may use the keyword a lot, while for other keywords, you might not use it at all. The key here is to write for the user experience. And if you’re thinking about keyword density being a ranking factor, I would ignore this metric completely.

Even in my own SERP Analysis, I checked top-ranking pages and discovered they ranked for dozens of additional keywords that weren’t even mentioned on the page. In fact, for these keywords that weren’t even mentioned, the pages were ranking on the first page for those search terms. That’s right, the pages were ranking on the first-page search results for keywords that weren’t even mentioned even once. You can see the analysis of keywords here.


When it comes to writing SEO optimized content, it’s best to focus on a single primary keyword. This keyword will be used in your title and url and within your content. Thanks to Google’s BERT, it’s not important anymore to use exact matches or lots of keyword viarants. In fact, over using keywords too much can be considered keyword stuffing and can hurt your SEO. Still however, it’s can be benefiticail to include your primary keyword and secondary keywords in your article as long as they sound natural.