What Are LSI Keywords And How To Calculate Keyword Density

color research word keyThere has been a lot of buzz about LSI keywords and how they help rank your content within search engines. LSI stands for “Latent Semantic Indexing” keywords and over the years they’ve started to play more of an important role in helping identify your content, even helping it rank higher within search engines. Before continuing further, let’s look at the definition of “Latent Semantic Indexing” or LSI. When you include LSI keywords within your content, you’re adding closely related terms into your content. For example, if one of my targeted keywords within my content is “building a website from scratch” then some LSI keywords would be: How to Start a Website From Scratch, Building a Website for Dummies, Make a Website From Scratch and How to Build a Website for Beginners.

As you’ve noticed, the LSI keywords are closely related to my main keyword phrase which is “building a website from scratch”. Google uses LSI keywords to further enhance the ability for them to determine the relevancy of your content. Several years ago, ranking content would consist of scattering keywords several times across the page causing content to sound unnatural or spammy. With “Latent Semantic Indexing”, search engines are looking for words related to your targeted keywords.

Going forward, you need the right combination of targeted and LSI keywords throughout your content. Here’s what you’ll learn within this blog post.

  • How to use Your Targeted Keywords to Find Relevant LSI keywords
  • How to Calculate Keyword Density
  • Checking Keyword Density Percentage
  • Optimizing LSI Keywords Within Content
  • The Seopressor Plugin

Moving From Targeted Keywords to LSI Keywords

The objective is to find words that are “related” to your keywords so that you can scatter them throughout your content keeping the flow very consistent. The rule of thumb is to use “2-3” LSI keywords per “targeted” keyword. For example, if my main keyword is “link building” then I’ll want to find 2-3 related keywords which are consistent with my content. The amount of LSI keywords you’ll use within your content will depend on the total length of your content.

So, how can you make the shift from “targeted” to “LSI” keywords? The Google Keyword Tool is mainly used for generating targeted keywords and NOT LSI, however finding LSI keywords can be simple if you know how to use the Google search bar correctly.

When typing a phrase like “link building” within the Google search bar, you’ll notice that the search mechanism will automatically generate a drop-down with closely related search terms. Even though many of these “terms” can be used as “main” keywords, you’ll be able to pull a few LSI keywords out of the bunch.

Here are two examples; first we’ll use the keyword “link building”


In this example, we’ll use “Wordpress plugins for beginners”


In both examples you’ll be able to pull out some “LSI keywords” that are related to your targeted keyword. Finding closely related keywords is the first step in effective LSI keyword research. Later I’ll be discussing the final step in narrowing down you’re research to optimal keywords to insert into your content.

There is another way to use Google search to generate a handful of LSI keywords. Once you’re done typing in your search phrase into the Google search bar, click “Search” and wait for the results to generate. Once you have the page of results, continue to scroll down to the bottom of the page where you’ll see Searches related to “”.

These phrases will be effective LSI keywords because they are related to your targeted word and are long tail keywords. Long tail keywords are phrases that people typed in that include more then 2-3 words within the phrase. These are perfect optimization keywords that can easily be ranked for in Google depending on the phrase. The mix of long tail and LSI will work well when ranking your content.


What’s next…

How To Find LSI Keywords Right For Your Content

Let’s check how effective these “LSI” keywords will be when inserted into your content. There are a few requirements to look for when narrowing down you’re keyword research. If these requirements are met then abort using the keyword or you’re going to have a tough time ranking for that LSI keyword.

  • If Keyword Will Make Sense When Inserted Into My Content
  • Looking for Phrases with “3” or “More” Words Within Them
  • Monthly Search Volume of Phrase
  • An Increasing Monthly Trend (Not Lowering Trend)
  • Total Search Results Less Than 150,000 in Google

Here’s the targeted keyword – “Wordpress Plugins for Beginners” and we’ll be generating “1” LSI keyword.

Here are the results from Google search…

Results from Drop-Down…


Results from Searches related to “”


Next, let’s head over to the Google Keyword Planner Tool so we can check out a few statistics…

I typed in the words generated by Google search into Google Keyword Planner to check Monthly Search Volume and Monthly Trend. Here are my results…


The LSI keyword I chose out of the punch is pretty obvious: WordPress Plugin Tutorial for Beginners

This keyword phrase has a monthly search volume of 90 and is increasing with the previous month averaging 110. If you do the match, it’s a potential 3.6 new visits per day and growing. Now remember, that’s only for 1 LSI keyword but if you have 6-7, then they can generate a lot of new visits to your website each month.

There’s one more final step left. Let’s check how many results are generated in Google for this EXACT phrase. The goal is to find keywords that have less than 150,000 search results within Google. Do a quick search using quotations “WordPress Plugin Tutorial for Beginners”

The results are awesome because there are only 117,000.


Once all you’re requirements have been met, it’s time to move to the next step which is calculating how many times you should insert an LSI keyword into your content.

How to Calculate Keyword Density

There has been much debate about the optimal keyword density of LSI keywords. The recommended range is between 2-3%. What does this mean?

You should have 2-4 LSI keywords per 100 words of typed content while keeping in mind that high quality content should be your first priority. This doesn’t mean that you should go stuffing nonsense LSI keywords into you’re content every 100 words creating a complete mess. This rule only applies if you have natural flowing content which, even with, LSI keywords embedded can still be achieved. If you can’t insert them every 100 words because it’ll affect the natural flow, then skip it until you find a spot after 400 words that’s more natural.

Now that we have a good indication of the keyword density percentage that you should be aiming for within your content, how can you calculate the EXACT density within your content if you’re not using a keyword density tool to automate the process? You need to start by keeping track of how often you inserted the “phrase” within your content. For example, if you inserted a LSI keyword 10 times within your content then make a note of it on a piece of paper. Next, you should easily be able to calculate the length of your content. Many word processor programs like Microsoft Word or Works will be display the number towards the bottom of your content. After you have both numbers, use this formula…

Checking Keyword Density Percentage

You’re doing this manually so it’s important to have the information you gathered handy. Each LSI keyword used within your content should be calculated separately. Once you have calculated the numbers for each, simply add them together to get your total keyword density percentage.

Here’s our example…

The LSI keyword = “Link Building Techniques” and it contains “3” words: “link”+”building”+”technique”

This keyword phrase was used 10 times within your content. You’re content length is 3000 words.

Keyword Density Percentage Formula:

10 * 3 / 3000 * 100 = 1.0%

Things to remember…

1) Each keyword phrase is treated separately by Google. If you’ve added up all keyword density percentages and they equal 9%, don’t be alarmed because each “phrase” will be treated independently. You should be concerned with individual LSI keyword density.

2) Calculating optimal keyword density manually can be difficult so use tools that are available to you. Do a simple “keyword density tool” or “word density checker” search within Google to find FREE tools that can help you.

3) Complete writing you’re content naturally then go back adding keywords where it makes sense. Sometimes if you add LSI keywords while typing, you’ll affect the natural flow of your content. Write out your content naturally then go back and add words which will help you keep the natural flow of your content.

4) Don’t worry about adding them every 100 words if you’re flow will suffer. Google has indicated that the importance of density is not a priority so scattering them every 300-400 words is fine.

For those of you using WordPress, there are easier ways to calculate keyword density within your content. Use the following plugins:

Optimizing LSI Keywords Within Content

It’s important that you place your LSI keywords in the right places, with decoration, to effectively optimize your content. For example, there are certain rules that must be applied to both your targeted and LSI keywords. We know from experience that the Title, URL and description must definitely include your targeted words. Targeted keywords must be scattered throughout your content including once in the opening and closing paragraphs. So how do you optimize your LSI keywords?

Here’s the basic LSI optimizing suggestions to follow. Apply these to at least “1” of your keywords…

Keyword in Content

1) Include LSI keyword in image ALT tag – If you’ve added images within your content then it’s good to have your keyword within the images ALT tag. WordPress helps streamlines this entire process through plugins however here’s an example in HTML: “<img src=”http://yoursite.com/image.jpg” ALT=”YOUR KEYWORD” />

2) Include LSI Keyword within the first 100 words – The keyword showing up early in the content helps search engines determine what your content is about. You can BOLD your keyword to add more emphasis to it.

3) Optimal keyword density – Try to achieve between 2%-4% so that you’re keywords are scattered evenly throughout your content. Don’t overdo it and keep the flow natural.

Keyword Decoration:

1) Minimum “1” LSI keyword should be bolded – This is important because it tells search engines what your content is all about. Bold your keywords few times but do not overdo it.

2) Include your LSI keyword within an H1 tag – Most WordPress themes automatically have an H1 tag for the title. If not, always make sure you have a H1 tag in your content. An example is: <h1>your title here</h1>

3) Include your LSI keyword within an H2 tag – These are usually sub-headings within your content. An example of the tag in HTML: <h2>your sub-heading</h2> followed by your content below that sub-heading. WordPress makes it easy to add a H2 tag when writing content. When creating a post, you can type your sub-heading, highlight it and select H2 from drop-down.

If you’re not happy using the H2 size and font because of preset CSS configuration, then use the H3 tag for sub-headings.

4) Minimum “1” LSI keyword should be italic (Optional)

5) Minimum “1” LSI keyword should be underlined (Optional)

Content/Page URL

1) Include your keyword within the URL of the post/page – You can use your targeted or LSI keyword. Determine which word has more potential by doing a quick “search volume” check within Google Keyword Planner. After, check the keyword trends over the last few months, is the search volume increasing or decreasing?

Seopressor Plugin

This SEOpressor Plugin is the best LSI keywords generator and it will help you streamline your entire research process. This plugin is available for people using the WordPress platform. Purchasing the plugin is optional but I’ve been using it and would recommend that you watch the video so you’ll understand how it can save you time and optimize you’re content automatically. Once you’ve installed the plugin, it displays all the information you need to optimize your content while you’re creating you’re post.

Read my complete SEOPressor Review


Watch Video – How to calculate keyword density using the SEOpressor Plugin…