Keyword Research Tools for Topic Clustering

Many Keyword Research Tools have no ability to understand connections between topics and themes. As such, they may work well for exact match PPC campaigns, but in a modern SEO strategy, they do not have the effectiveness of modern keyword research tools.

A keyword cluster represents a group of keywords that relate to the same user intent, these might slightly differ in how many words they contain but they essentially refer the same topic.

Let’s take an example of the primary keyword ‘London Hotel’, a keyword cluster could contain the following keywords:

Cheap hotels in London
London hotel deals
Best hotels in London
5-star hotels in London

Creating a piece of content based on a keyword cluster has many benefits:

Improves the ranking for short and long-tail keyword variations
Helps create a content plan for the writer
Increases internal linking possibilities
Provides value to the reader

We Compared 6 Keyword Research tools around a practical example:

This is a Keyword Research Tools Review which is useful. We created the keyword research reports on five tools, all using the same starting point – to develop a content plan around the concept: “Shopify SEO”.

We looked at 5 tools:

Inlinks
Google Planner
Semrush
Ahrefs
Keyword Insights
Ubersuggest

The Top-Line Results

In case you don’t want to consider the nuances between the tools, here are the absolute numbers in an easy to compare table.

Product	Total Keywords	Total Volume	Quality of Clustering	Shows Questions?	Monthly Cost
InLinks	1410	4.4K	Great	Yes	39$
Google KW Planner	179	4.7K	Great	No	GA
SEMRush	1.6K	20K	Great	Yes	120$
Ahrefs	1.6K	5.2K	Great	Yes	99$
Keyword Insights	635		Great	Yes	49$
Ubersuggest	194	4.2K	Average	Yes	12$

This table tells only part of the story

The InLinks Keyword Research Tool:

In addition to offering internal linking/schema automation and SEO content optimization features, InLinks provides a keyword research tool for creating a content brief targetting a seed keyword which can be used to build your topical clusters.

InLinks’ keyword research tool also provides questions related to the main primary keyword, these can be useful to build an informational topic cluster:

Google Keyword Planner:

The Google Keyword Planner is a keyword research tool available within a Google Ads account, we did research starting with the primary keyword ‘Shopify SEO’ and got the following:

As we can see in the screenshot above, there are several keywords having a commercial user intent. We can optimize our content around those 5 keywords and therefore increase our chances of ranking for all of them.

The Google Keyword Planner provides keyword ideas along with the average monthly searches and search trends compared to the last 3 months and the last year.

The competition column shows how competitive it is to place an ad in the paid results for a given keyword, it’s not a metric on how hard it is to rank a page on the 1st page in the SERPs.

The Google Keyword Planner is a good place to start building your keyword clusters if you have an active account on Google Ads, the search trends data can help you select keywords that are currently going up in the trend and ignore others that are decreasing in trend.

Pros: Use the Google Keyword Planner if: You need a free tool

Cons: It would have been nice if this tool provided related questions and competitive metric that relates to ranking in the SERPs.

SEMRush Keyword Magic Tool:

SEMRush has a comprehensive keyword research tool named ‘Keyword Magic Tool’, we applied the same steps as above and got the following:

Building a keyword cluster with this tool is a seamless process, simply put in your primary keyword and then select the relevant related keywords to be saved in the ‘Keyword Manager’ section (you can then export the keyword cluster into an Excel sheet or CSV file).

There are some interesting filtering options based on monthly search volume, keyword difficulty and search intent. In addition, if you click on the ‘Questions’ you’ll see a list of questions about the primary keyword (useful for an informational keyword cluster).

SEMRush Keyword Magic Tool is a complete keyword research tool that provides substantial data to help set up your keyword clusters, we particularly like the ‘Keyword Manager’ section where you can save your keyword lists and export them to an Excel sheet.

SEMRush pricing plans start at 120$ / month, so not the cheapest option on the market.

Ahrefs Keywords Explorer:

Ahrefs Keywords Explorer provides somewhat similar options to Semrush except for a few differences:

Setting up a keyword cluster on Ahrefs Keywords Explorer is also a straightforward process, you can select the relevant keywords and save them in a list to be reviewed or exported to an Excel sheet. There’s a keyword difficulty metric provided for each term which is an estimation of how hard it is to rank in the top 10 results, average monthly search volume and a column ‘TP’ for Traffic Potential which is an estimation of the organic traffic to be acquired if a site ranks in the #1 position.

This tool also provides questions related to the primary keyword, same as Semrush this could be useful to build an informational keyword cluster:

Ahrefs Keywords Explorer is a solid tool that enables you to build keyword clusters and provides all the relevant data to help you select the terms you want to rank for. The pricing of an Ahrefs account starts at 99$ per month.

Keyword Insights

Keyword Insights specializes on keyword clustering and context, it comes with its own keyword research tool named ‘Keyword Discovery’. We applied the same steps described above and got the following:

We got 635 keywords related to the seed term of ‘Shopify SEO’, in addition to their corresponding monthly searches, competition metric and CPC value.

We exported this list into a .CSV file and imported it to ‘Keyword Clustering’, the following is the Excel sheet that contains the clustering along the context and the suggested titles:

Based on this sheet you can built individual pages while covering the keyword variations that belong to each cluster.

Ubersuggest

Ubersuggest is an affordable keyword research tool compared to Semrush and Ahrefs, it offers a 7 day free trial period. The same keyword research as previously gives the following:

Setting up a keyword cluster is easy on Ubersuggest, you can select the search terms and save them to a list to be exported to a CSV file. A volume column displays the monthly search volume for each keyword and an SEO Difficulty column estimates how competitive it is to rank for each term in the Serps.

As far as the questions, we found them to be not that accurate compared to what we saw with other competitors:

Ubersuggest is a cheaper alternative to Semrush and Ahrefs (pricing plans start at 12$ per month), it provides all the basic options to build keyword clusters and analyze the main metrics such as search volumes and SEO difficulty.