11 Best Keyword Research Tools For SEO [2023 Reviews]

You don’t need me to tell you keyword research is important, as is finding the best keyword research tools for that purpose.

Or maybe you do.

You shouldn’t though.

Because if you make a mistake here you’re going to achieve the SEO equivalent of emptying your bladder over the side of a ship…during a hurricane.

You know you need a great keyword tool, but the problem is there are literally dozens of them on the market.

They all make the same promises – like revealing those untapped keywords nobody, anywhere knows about.

But how many of them actually deliver?

That’s what we’re going to look at today – testing and evaluating the best keyword tools for SEOs and affiliate marketers.

Best Keyword Research Tools

Here is the list of best keyword research tools we’re reviewing in our post:

Google Keyword Planner (Free)
Ubersuggest (Free)
Keywords Everywhere (Free)
Answer The Public (Free)
Google Search Console (Free)
KWFinder (Paid)
Moz Keyword Explorer (Paid)
SEMRush (Paid)
SERPStat (Paid)
Ahrefs Keyword Explorer (Paid)
SE Ranking (Paid)

What Is A Keyword Research Tool?

Okay, before we get into the nitty-gritty of the different tools, I thought it might be a good idea to take a second here to explain what they actually do.

A keyword research tool is a piece of software or web service that allows you to achieve one of two key goals:

Generate a list of related keywords based on a “seed” keyword
Evaluate how competitive a given keyword is

You do this by typing your keyword into the search field of your keyword tool of choice:

And it generates a list of keywords related to your original search term by harvesting data from one or more data sources – typically from search engines.

Most other blog posts on this topic try to divide keyword tools into categories of either “traditional” or “competition”, but I don’t see the point in doing that.

Why?

Because the free tools all tend to be traditional in that you type in a seed keyword and they generate a relatively useful list of results.
And almost all paid keyword tools offer some kind of URL or competitor analysis function, in addition to being “traditional” tools.

Why Even Bother Using A Keyword Research Tool?

This is a valid question.

After all, why not just come up with your own keyword ideas and start creating content around them?

Sure, do that as long as you’re okay with throwing away the next few months of your life.

Keyword tools are worth using for two key reasons:

Time
Data

Not only do they directly speed up the research process, but they give you the keys to a myriad of insights you otherwise wouldn’t have access to.

The goal, of course, is to uncover ‘easy to rank’ search terms that’ll offer a positive ROI.

It would take you hundreds of hours to produce the same results even the crappiest keyword tool can spit out in under 30 seconds.

Useless trivia: Once upon a time ago, I actually did manual keyword competition research for a niche site.

I cried a lot that weekend.

Why using a keyword research tool makes sense:

They enable keyword ideation – suggesting keywords you’d never have thought of
They offer you insight into consumer behavior and search patterns
You can evaluate markets/niches before building sites in them
Find relevant keywords for your audience i.e. search intent
Reverse engineer your competitor’s keywords

Basically, they give you the kind of information that allows you to strategically target keywords as opposed to shooting blind.

Another benefit is they provide a framework to create content around – you will have keywords that are statistically proven.

The Best Free Keyword Research Tools

Let’s take a quick look at what free keyword tools are available to you, and whether they’re worth spending a lot of time on.

Hint: They’re not.

1. Google Keyword Planner

This is the OG of keyword research – the grandpappy of all keyword tools.

For a long time, this was the data source for pretty much every keyword tool on the market

Or it was until Google changed its mind about sharing data with marketers.

Because Google hates SEOs and affiliates…allegedly.

What most marketers forget – or choose to ignore- is that the Google Keyword Planner is part of the Google Ads (formerly Google AdWords) platform.

So its original purpose was as a PPC (Pay per Click) research tool, and not as an organic keyword tool for SEOs or affiliates.

Entering a search term into the Google Keyword Planner (GKP) will give you:

Related keywords
Average monthly searches for each keyword
Competition (Low, Medium or High)
CPC (top of page ad) values

As a basics “ideation” tool the GKP is fine…but:

The “Average Monthly Searches” metric is pretty much useless.
I would never build a website based on their keyword competition data. Ever.

What the Google Keyword Planner did well was to provide you with a quick and easy way to generate a list of related keywords for a niche site.

But – as of the time of writing- you need to add a payment method to your AdWords account before you can use the GKP properly.

Basically, the Google Keyword Planner has had its day, and it’s time for people to move on.

Best feature

It’s free.

Worst feature

It’s not free – you have to set up a payment method to use it.

Then you can add in everything else, like the pre-millennium interface, and search volumes so vague they could run for political office.

2. Ubersuggest

Once upon a time, this was Ubersuggest.io.

But Neil Patel saw the huge potential in this free tool and acquired it a few years ago.

Since then the development team has spent a lot of time adding new features to it, making what used to be a barebones “autocomplete tool” far more visual, and far more useful.

The frontend shows you search volume, keyword (SEO) difficulty, paid difficulty and CPC data.

A nice touch is that it also displays annual search volume trends, so you can plan around those seasonal lulls.

The actual keyword research tool shows you a good number of keyword suggestions:

But it also displays your top competitors in the SERPs for whatever keyword you’re researching:

You can also choose to simply reverse engineer what your competitors are doing by analyzing what keywords their domain ranks for, how much traffic they generate and even how difficult it might be to outrank them.

And even which pages on their domain get the most traffic, data you’ll rarely find outside paid premium tools.

So, Ubersuggest is more than just your average keyword research tool – it’s a suite of tools.

Best feature

The SERP analysis features are excellent considering this is a free tool.

Worst feature

The keyword difficulty score is way off right now.

Click Here To Check Ubersuggest

3. Keywords Everywhere

There’s a certain amount of beauty in simplicity, which is what I like so much about Keywords Everywhere.

This plugin for Google Chrome or Mozilla Firefox provides you with some extra data via the Google API.

Doesn’t sound all that exciting, does it?

But the fact that the data is available within your web browser makes it instantly accessible – you don’t need to login to anything else.

That simple feature alone won this tool a lot of fans.

In addition to displaying “related keywords”, it also lists dozens of other keywords that “People have also searched for”.

So you get an at-a-glance overview of what types of keywords are related to your seed keyword, an approximate search volume, CPC data, and even a competition score.

Keywords Everywhere is what Google Keyword Planner should have evolved into.

The downside here is that you’re relying on Google’s keyword data, which they’re doing their very best to hide from the general public.

Best feature

Do keyword research directly within your web browser.

Worst Feature

Relies solely on whatever data Google chooses to share via their API.

Click Here To Check Keywords Everywhere

4. Answer The Public

This is a keyword tool that does something very simple, but incredibly valuable – it generates a list of keywords based on Google’s AutoComplete feature.

It’s not the only keyword tool that does this, but it’s more accessible than anything else I’ve come across.

Oh, and it’s free.

It basically takes your seed keyword and then applies a number of modifiers to it such as:

Prepositions (to, with, near, is)
Comparisons (or, and, like, versus)
Alphabetical (seed keyword + a to z autocomplete)

It also generates questions and “related searches” based on your original seed keyword.

Its “unique feature” is that it presents keyword data in a visual format.

Here’s what that looks like:

That looks cool, right?

It is, but only if you want to develop neck, back, and shoulder strain.

Fortunately, you can also arrange the data in table format.

If you’re looking for a free keyword research tool that generates massive lists of long-tail keywords, you could do a lot worse than check out ATP.

Best feature

It automates the process of harvesting long-tail keywords from Google, free of charge.

Worst feature

There are no filtering options. None. You have to download CSV files and do it manually.

Click Here To Check Answer The Public

5. Google Search Console

Oh, we’re adding Google Search Console to the list?

Yes, and for entirely valid reasons.

Obviously, Search Console can only be used if you have a website with traffic coming to it.

So if that’s not you, then skip this bit and head over to the paid keyword tools section of our review.

The thing is that very few webmasters (is that still a word?) pay attention to all those extra, and very specific, keyword queries you’ll find in Search Console.

There’s keyword gold in them thar hills!

You can use these keywords to either optimize your existing pages or to create a brand new piece of content around:

And – as the screenshot says – you won’t find these keywords in most tools.

Why?

Because some of them have never been searched for before – Google estimates that there are something like 2 trillion never-before-seen keyword searches every single year.

Best feature

It’s one of the only ways you can find out exactly what keywords people use to find your site. Yes, you can do that in Google Analytics, but only when you link it to Search Console in the first place.

Worst feature

It’s not really a keyword research tool…but I still love it.

Honorable Mention

Keyword Shitter

This isn’t a keyword research tool in the true sense of the word.

Instead, think of it as more of an idea generator.
It’s not even remotely refined – you just type in a search term and it starts…well…pooping out related keywords.

Probably the best use for Keyword Shitter is if you’re having a bout of keyword researcher block.

Instead of just staring at your screen going “…I got nothing…I’m wasting my life”, let this tool throw some ideas your way.

So now that we’ve taken a look at the free keyword tools it’s time to take on the big hitters of the keyword research industry.

oh, do tell me how your free keyword tool is better than a paid one

The Best Paid Keyword Research Tools

In an ideal world, free keyword tools would be just as powerful as ones that cost anywhere from $29 to $99 per month.

But we don’t live in an ideal world.

There are dozens of different paid tools on the market, so there’s no way for us to cover every single one of them in a way that’s useful to you.

I mean, what’s the point in us reviewing 15 or 20 keyword tools you’ve:

Never heard of
Will never use

We simply do not want to waste YOUR time.

Something else to consider is that the days of dedicated keyword research tools are over and done. Any of the paid tools we list here are part of an overall suite of SEO tools.

So they’re hybrids rather than dedicated research tools.

In fact, some of the dedicated, old school keyword tools have been left behind as a result of this change in user needs and expectations.

That’s just the nature of this game – you either compete or you become irrelevant.

And you’ll probably be surprised at how quickly certain premium tools are becoming old news.

Our Assessment Criteria

When we were putting together the refresh of this review we decided to put ourselves in the shoes of the average digital marketer and ask one question:

What features of a keyword tool are most important to you?

The reality is that most of you really only care about a handful of features in any of these tools, such as:

Number of related keywords generated for each search
A keyword difficulty score that’s not a total and utter lie
How competitive the SERPs are (snippets, etc)
Being able to manipulate and collate keywords within the tool
So that’s exactly what we measured.

1. Keyword Difficulty

Ask any sensible affiliate marketer or SEO what one specific keyword metric they really care about, and they’ll most likely tell you it’s keyword competitiveness.

But keyword difficulty scores vary wildly from one tool to the next, so how can you tell which one is correct?

The honest truth is that you can’t and shouldn’t put all your faith in a keyword difficulty score.

Just because Tool X says a keyword has little or no competition doesn’t mean that’s true.

It simply means that according to the tool’s internal metrics, this is how difficult it will be to rank for that specific keyword.

You should always, always, manually check the SERPs before building content around a keyword.

Basically, ask yourself if you can publish a better blog post than your ten competitors.

And can you get more backlinks to that page than they have?

2. Keyword Suggestions

Having the most expensive keyword tool on the market might make you feel better about yourself.

But unless it can churn out several hundred (or thousand) keywords for you to analyze and choose from, then you’re probably wasting your time.

Now, the caveat here is that search volumes should never be treated as absolutes – regardless of what keyword tool you use.

Why?

Because some tools use third party data sources (Ahrefs), while others use Google’s data (KWFinder).

So you can’t compare oranges with oranges here.

Equally, you cannot rely on Google to accurately report search volumes because it’s not in their interest to help SEOs or affiliates make informed decisions on this stuff.

3. Data Filtering

It’s easy to become overawed by how many keywords a specific tool can suggest.

But sheer volume by itself isn’t useful.

In fact, it can hinder you unless you have ways to filter through your keyword data in an effective manner.

You’ll see later in this review how certain keyword tools spat out anywhere from 19k to 32k keywords for a single search term.

How would you feel about exporting 32,000 data fields, and then having to filter through them in Excel or Google Sheets?
Exactly.

You can stop crying now.

4. SERP Analysis

Personally, I put a LOT of emphasis on this one feature.

As much as I love a good ole’ keyword difficulty score, it’ll be a while before it fully replaces a manual SERP analysis. (Though I’ll be happy to eat my words when it does.)

Why is SERP analysis so important?

Well, assuming we have the right data in front of us, humans are still much better at evaluating keyword difficulty.

Human beings are pattern matching and recognition “machines”.

It just takes us longer to do it, but we can interpret the data in a way no AI system currently can.

So, while I recommend using a difficulty metric to narrow down your suggestions, you should always do a manual analysis before giving any keyword the green light.

As I briefly mentioned earlier, your ability to do this effectively relies on data.

The availability and accuracy of specific kinds of data, like:

Backlinks
Referring domains
Domain level authority
Page level authority

Now that you understand our logic, let’s look at how well our selection of paid keyword tools performed based on the above measurements.

1. KWFinder

This is one of those tools that could have disappeared off the radar, but thankfully it didn’t.

There’s a lot to like about KWFinder because there’s a lot going on underneath the hood.

It’s basically Budget Ahrefs, but don’t let the “budget” tag fool you.

The first thing we have to give props for is the interface.

It’s nice to have one that was obviously designed for the end-user…not for the developer.

Okay, at first glance this screen looks really busy.

But you get used to it very quickly, to the point where you feel kinda weird using other tools that don’t offer the same unified view of your data.

I personally love that I don’t have to open a separate tab for SERP analysis, keyword difficulty, related keywords, search volume trends, etc., etc.

Keyword Suggestions

The free version of this tool is limited to 50 searches, which is fine.

But when you look at the paid versions (including their Agency package) you’ll see you’re limited to 700 search results per keyword.

Now, I know some people won’t see a problem here, but I do.
700 searches per keyword is pretty poor when compared to other tools that can give you tens of thousands of keyword results, and all without breaking a sweat.

The question(s) I ask myself here is: How many keywords aren’t being returned…and are they the ones with the most value?

Keyword Filtering

One aspect of KWFinder that’s head and shoulders above most other tools we reviewed is the data filtering.

I find it really intuitive and it’s quick AF too.

Sort by min/max search volume
Include or exclude specific keywords
Choose how many words your phrases should have
Only display keywords of a certain difficulty level

Keyword Difficulty

KWFinder bases its difficulty score on a number of different metrics, including Moz and Majestic.

The sample keyword we’ll use throughout this review is “dog harness”, and when we ran it through KWFinder we go this result:

56/100 indicates this is a really tough keyword to rank for, but you’ll see how that compares to other keyword tools later in the review.

SERP Analysis

Your SERP analysis data is available right from the main screen – there’s no need for additional tabs or windows.

From left to right you have Domain Authority, Page Authority, Citation Flow, Trust Flow, Facebook shares, Link Profile Strength and Estimated Visitors.

We have no idea why they include how many Facebook shares a URL has, especially considering Facebook content isn’t indexed by Google.

Note: One feature I’d love to see in KWFinder is collapsible panes- like being able to minimize the SERP analysis window so you can just focus on finding more keywords, and vice versa.

This is a keyword tool with a bright future ahead of it – it has already left some of its more expensive competitors eating its digital dust.

Best feature

They completely nailed the interface – it’s hard to find fault with it.

Worst feature

The limited number of returned searches (700) is the lowest of any of the paid tools in this review.

Suitable for

SEO’s or affiliate marketers on a tight budget but who need access to premium quality tools.

KWFinder Summary
Keyword suggestions		KD scoring
SERP Analysis		Data Filtering
Interface		Price

Click Here To Get KWFinder

2. Moz Keyword Explorer

If you’ve been around the SEO scene for more than a few weeks you’ll have already heard somebody mention Moz.

It used to be SEOMoz, but they dropped the “SEO” part a few years back.

Anyhoo, they’ve been around since 2004, so they know a thing or two about keyword research.

Moz Keyword Explorer uses clickstream data which according to Moz is “…the data collected during clickstream analysis which includes pages a user visits and the sequential stream of clicks they create as they move across the web, hence “clickstream data”.

Or to put it another way, this is data collected from a wide variety of sources besides Google i.e. other search engines, mobile apps, data mining tools, etc.

Why not use Google’s data?

Because Google is doing its level best to hide data from SEOs and marketers.

It’s not unreasonable to believe that Google will eventually turn off their free keyword data faucet.

I like the way Moz presents their keyword data – it’s modern and visually appealing. You don’t have to spend very long figuring it out.

And you might also have noticed that along with all the usual stuff (search volume, keyword difficulty, etc.) Moz also displays ‘Organic CTR’ and ‘Priority’ scores.

Organic CTR represents the lack of other SERP features that distract searchers from clicking on organic links. Higher is better.

‘Priority’ is a combined calculation of search volume, ‘Organic CTR’ and keyword difficulty. Again, higher is better.