How to Use Latent Semantic Indexing Keywords to Boost Your SEO

Updated February 3, 2023

What Does LSI Stand For? 

LSI stands for latent semantic indexing. Also known as latent semantic analysis, LSI is a concept that helps search engines like Google classify and retrieve information. Using a series of mathematical equations called singular value decomposition (SVD), they scan unstructured data and establish connections between terms.

Until latent semantic indexing was included in algorithms, it was difficult for search engines to understand related keywords and related terms. 

Understanding latent semantic indexing can help inform your digital marketing and strengthen your search engine optimization. Your SEO strategy should include With thorough keyword research, your team can create content that targets multiple, but related, keywords.

While LSI can sound complicated, understanding of LSI doesn’t require a degree in computer science. It is actually a concept anyone who has conducted an internet search is familiar with, particularly if that person has some basic knowledge of keywords and SEO.

To understand how LSI works, you need to know that search engines are smart enough to identify the context of your content and synonyms related to your keywords. While a lot of people think that LSI keywords are simply synonyms, this is incorrect. LSI keywords are simply words that are frequently found together because they share the same context.

For example, “Apple” and “iTunes” are LSI keywords because they share the same context and are frequently found together. But they are not synonyms.

If your page or blog post is about Apple, how will a search engine know if you’re referring to the fruit or the company?

Answer: It looks for LSI keywords. Take this example:

• If your page contains the words “baked apples,” “red apple,” “green apple,” “apple nutrition,” “Fuji apples,” “honeycrisp apple,” and/or “eating apple,” the search engine recognizes that your page is most likely about the fruit.
• If your page contains the words: “iTunes,” “Apple Hulu,” “Apple news,” “Apple stores,” “Apple iPhone,” “Apple iPad,” “Apple stock price,” and/or “Apple campus,” then the search engine understands your page is most likely about the company.

As you can see from this example, you will need to know which LSI keywords will make a difference to your specific rankings in order to be successful, which can be a challenging task. 

Why Search Engines Started Using Latent Semantic Indexing

In the past, regular keyword searches approached a webpage with an accountant mentality – the page contained a given word or it didn’t, with no middle ground. The only measure search engines had for the relevancy of a page to a given search was keyword density.

This led to a practice known as keyword stuffing, a practice of putting keywords in multiple places in the text in as rapid a succession as possible. 

Other examples of keyword stuffing include adding lists of phone numbers without substantial added value or adding blocks of text listing cities and states for which the webpage is trying to gain SEO ranking.

Google, in particular, started penalizing websites for keyword stuffing. Google also began to move away from keyword density, looking instead at LSI keywords.

LSI helps search engines better understand the meaning of a search query and the meaning of a webpage., and that improves the match between what people search for and what they find in the search results.

The Benefits of Using LSI Keywords:

LSI keywords have advantages for both SEO and user experience. There are several benefits of having LSI keywords in your content:

• LSI prevents your content from being labelled as spam in the eyes of search engines.

Having varied mentions of keyword phrases that are semantically related to your primary keywords increases your content’s credibility. If someone finds your site through a search engine but doesn’t find the content he or she is expecting, that person can report you to the search engine as a spammed. 

• LSI keywords help you reduce bounce rates by preventing your site from ranking for the wrong terms.

For example, if you are selling Lenovo Notebook computers, you do not want the search engine traffic from those seeking information about the 2014 movie “The Notebook.”

• LSI keywords will help you retain visitors on your site by making the flow of content natural and meaningful.

This gives your readers a peaceful environment without making it feel stuffed with keywords. This also differentiates your content from keyword dense content, which simply repeats keywords and key phrases to dupe the search engines into giving a high ranking. 

• LSI can help your site rank better for related searches.

Search engine bots automatically crawl your site and make a perception about the content. LSI keywords will rank your site for semantically related searches, no matter what your target keyword. For example, if you include LSI keywords for a business selling custom greeting cards at a premium price, your LSI keywords should allow you to skip searches for “inexpensive” or “print at home” greeting cards.

• LSI keywords can increase sales by helping your business rank higher with less competition.

For example, Amazon records an amazing 57% of all sales through keywords that are LSI versions of the primary keyword.

Overall, LSI keywords help you get your website content in front of even larger audiences.

How to Create LSI Keywords

There are several “premium” tools on the market for generating LSI keywords, but a business does not need to incur a lot of cost to venture into LSI. There are several free tools that can help you generate LSI keywords for your website:

• Google Autocomplete. The easiest way to find LSI keyword is to choose one main keyword and put in Google search bar. Google automatically provides the best matching phrase or list for your primary keyword as you type it in the search bar.

• LSI Graph is a free SEO tool which generate LSI keywords for you. Just put your main keyword in the search bar and the tool will generate a list of relevant keywords for you.
• Niche Laboratory offers keywords suggestions, top ranking websites, website page titles, website meta descriptions, web site meta keywords, and a website competition matrix. This is a very helpful tool to find the best LSI keyword matches, as well as get an idea of a competitor’s traffic-driven keywords.

Finding the right LSI keyword tool will depend upon your content management system, goals, and search engine advertising strategy. However, you should not have to spend the money on a premium LSI tool to produce effective results.

How to Use LSI Keywords

LSI keywords should be added throughout your website’s pages, but the usage needs to sound natural and appropriate. Some of your LSI keywords can be synonyms for your main keyword and, therefore, can simply be substituted for your main keyword.

Here are the main places you should use your LSI keywords:

• Page title
• H1 and H2 tags
• URL address
• Meta tags
• Images alt text
• First paragraph of text
• Link and anchor text
• Last paragraph of text

As with your main keyword, try to avoid over-optimizing your site for any particular LSI keyword. Overusing an LSI keyword may be seen as keyword stuffing and will incur a penalty from the search engines. A good rule of thumb is to use each LSI keyword just once on a page.

Learn 5 beginner's steps for optimizing your business's website.

The Importance of LSI Keywords

The initial implementation of LSI was in reaction to many attempts by site owners to manipulate SEO. Until LSI, page content and meta tags were often long sets of needlessly repeated keywords with no recognizable information or topic.

LSI allows search engines to give credit to quality web page content. Therefore, by including semantically related search phrases in your page’s SEO copy, you are giving the search engines a better understanding of your page, company, products, and services.

Using LSI keywords makes the search engines, and your website visitors, happy. Quality content keeps around visitors once they have arrived, which increases conversion rates and your website's effectiveness.