8 free SEO keyword research tools to explore

Why is keyword research important?

Content teams conduct keyword research to identify the words and phrases that people use to search for goods, services and tips. They also perform this research to learn how those phrases rank based on their search volume in a given month. Content teams can use this information to develop and maintain a successful content strategy and understand what content their audiences want to see.

An organization's initial SEO strategy for its website or blog is just the start of the journey. Content marketers should continuously perform keyword research as part of their marketing efforts, because search engines like Google frequently change the algorithms that determine how content ranks. Teams that continuously monitor and optimize content on webpages can stay up to date on algorithm changes.

Teams can find many free tools online to help them gather information to develop and improve their content and SEO strategies. Organizations that want to perform keyword research for free should consider the following SEO keyword research tools.

This list was compiled based on a combination of market reports and vendor rankings from Gartner Peer Insights, Capterra and G2, plus additional research by Informa TechTarget editors.

1. AlsoAsked

AlsoAsked is a keyword research tool that can help organizations discover questions people ask around keywords and related phrases. As search engines have become more sophisticated, people increasingly use natural language prompts to conduct searches, and AlsoAsked can help organizations understand these questions. The tool also helps to identify search phrases, plan content and get the right content in front of potential customers.

Moreover, this tool offers results for long-tail keywords -- phrases that build on shorter keywords and are more specific -- and shows the relationships between these topics and questions.

AlsoAsked offers free credits during its trial period, then splits into three paid tiers.

2. Google Ads Keyword Planner

For marketing teams that run pay-per-click search campaigns, the Google Ads Keyword Planner tool can separate a targeted keyword list between SEO and pay-per-click (PPC) targeting. This tool also shows keyword suggestions and search volumes that can drive insights for campaign planning. Additionally, it shows a breakdown of cost-per-click data, advertising competition and seasonal traffic changes.

Teams that already do PPC advertising can benefit the most from this tool, as they can use the search volume feature for their campaigns. Yet, to access the most detailed analysis features for paid campaigns -- rather than just search volume ranges -- organizations must spend a certain amount of money on their paid Google Ad campaigns.

3. Google Search Console

Content teams can use Google Search Console to begin their keyword research and gauge how well their organization's web content performs on Google. This free tool analyzes the current keywords on a webpage and shows their average search engine results page (SERP) position, impressions and clicks.

Teams often use Google Search Console alongside other Google services for web and analytics tracking. Web administrators and content creators can use this tool to learn which pages receive minimal traffic and require changes. The tool can also show which search queries bring in the most traffic, so teams know which topics to cover in upcoming blog posts.

For example, users can combine Google Search Console with a Google Analytics account to get in-depth keyword data and find opportunity keywords -- phrases that rank in positions eight through 20 with a large number of impressions -- from the performance report. This report shows how Google ranks keywords in search queries from a snapshot in time. Content teams can use these opportunity keywords, along with on-page SEO improvements, to boost their page's SERP rankings.

This tool is free to use.

4. Google Trends

From the Google Trends interface, content teams can see a search term's popularity over time. This tool enables users to research individual words or compare keywords to see trend fluctuations, such as by season, holiday or annual releases of new technology.

For example, if a business sells a lot of Mother's Day products, Google Trends can show when keywords related to Mother's Day start to increase or decrease in search volume. That way, marketing teams can best prepare when to launch Mother's Day-related content and deals.

This tool also shows interest by region, breaks down time ranges, and shows related topics and search queries. It is free to use.

5. Keyword Surfer

Keyword Surfer is a free Google Chrome extension that analyzes Google search results directly on the SERP. This extension aims to assess the query volume for a given keyword in the Google database, which includes results from multiple countries. Within the SERP and search bar, users can see global estimates, their country's results and the top 10 similar keywords in the search results.

The Keyword Surfer extension is free to add to Chrome browsers.

6. Moz Keyword Explorer

In addition to its paid subscription options, Moz offers a free version of its Keyword Explorer tool. The free tool, which offers 10 queries per month, can benefit content teams that lack SEO experience. The tool doesn't include as many data points as some other tools, but that also makes it less overwhelming for new users.

Moz also creates a priority score, which gives content teams insight into whether they should invest time and effort into a keyword. The tool calculates priority scores based on various metrics, such as volume, clickthrough rate and difficulty, as well as how the organization prioritizes the keyword for its business.

7. Ranktracker

The most effective keywords for organizations to rank for aren't always obvious. Although certain words and phrases may be specific to products, services or industries, people often search using variations of those words and phrases.

To find useful keywords or phrases for search ranking viability, organizations need to know all the possible variations of potential keywords and phrases. Ranktracker is a keyword research tool that combines multiple tools into one to give users a multitude of keyword ideas. It can show a keyword's traffic potential and its SEO competition.

Ranktracker offers a seven-day free trial for its four paid plans.

8. Semrush

Semrush offers paid plans for its SEO tool, with free trials, which can benefit content teams just beginning their research. Semrush also offers a range of free keyword tools, with visibility into organic search rankings and search volume data, as well as a competitive keyword gap analysis.

Semrush's tool has backlink analysis for teams that want to identify which links direct back to their sites. Additional features, such as an SEO content template and topic research for content strategy planning, make this tool a viable option for teams that want to start SEO planning and building a strategy, but intend to eventually scale up to a subscription.

Editor's note: This article was updated to reflect changes in product information.

Griffin LaFleur is a MarketingOps and RevOps professional working for Swing Education. Throughout his career, LaFleur has also worked at agencies and independently as a B2B sales and marketing consultant.