5 Best Free Keyword Research Tools for Advertisers & Marketers in 2025

Keyword research is, or should be, a basic step in the creation of search engine marketing (SEM) campaigns. This step allows you to gauge what competitors are doing, what your customers are searching for, and which keywords are going to get you seen. The keywords you choose to support your campaign ultimately determines your success or failure, especially if you are running pay-per-click (PPC) ads.

Because keyword research is so important and could be potentially time-consuming, there are lots of tools being created out there. The good news is that you can create a list of profitable keywords without paying much or anything at all!

Google Keyword Tool

This free tool is available through Google AdWords and is pretty much an obvious choice when it comes to keyword research. This tool allows you to see what keywords your competitors are ranking well in organically and how popular the keyword is. If you don’t know where to start, you can even insert your URL and see what keyword Google thinks are relevant to your site and exclude or increase the bids accordingly.

Keyword Tool

Keyword Tool is free to use with limited features. The pro version will start at $38/month if you opt to pay annually. Here you can view suggested keyword lists for different search engines including Google, YouTube, Bing, Amazon, or the App Store. If you choose to pay for the pro version, you can see them sorted by search volume, cost-per-click, and intensity of competition, an offering that shows little added value over the Google AdWords Keyword tool.

SpyFu

SpyFu has a lot of different tools to be used in search engine optimization (SEO) and PPC research and could potentially be everything you’d need if you pay for pro versions. The basic tool is the SpyFu Classic which provides the daily AdWords PPC budget, average ad position and number of advertisers, top 10 paid keywords, and much more after just entering a domain on the home page.

SEMRush

SEMRush is a website analysis tool that provides an analysis of organic traffic and PPC ads and keywords. It is on the more expensive side should you decide you need the whole professional package, but they do offer a free trial. For simple keyword research, however, you can find the top competitors, top keywords complete with average positions, volume, and cost-per-click, as well as top a full competitive analysis after entering a website from the home page. Much like SpyFu’s Classic tool but with better data visualization.

WordStream

WordStream keyword tools help with research, suggestions, keyword analysis, and even recommendations for negative keywords – and there are quite a few different keyword tools offered for free. The interface is a bit like Google AdWords but is even easier to use for most and provides a full range of specific information.

SEM research can be a bit overwhelming and confusing without the right tool. With a little bit of digging and experimenting with the platforms listed above, you’ll be able to better understand how to not only generate traffic to your site, but ensure that it is the profitable kind of traffic.