Keyword research is the foundation of SEO. It reveals what your audience searches for, how they phrase their queries, and what content you should create. This guide covers the methodology, tools, and strategies for effective keyword research.

What is Keyword Research?

Keyword research is the process of discovering and analyzing search terms that people enter into search engines. The goal is to understand:

  1. What your target audience searches for
  2. How they phrase their searches
  3. Why they’re searching (intent)
  4. How difficult it is to rank for each term

This information guides your content strategy and helps you create pages that match what people are looking for.

Understanding Search Intent

Search intent (or user intent) is the purpose behind a search query. Google’s systems are designed to understand and match intent.1 Misaligning with intent is one of the most common SEO mistakes.

The Four Types of Search Intent

Based on the taxonomy developed by Andrei Broder at AltaVista and later refined by Google’s Search Quality Rater Guidelines:2

1. Informational Intent The user wants to learn something.

  • Examples: “what is seo”, “how to bake bread”, “python tutorial”
  • Content type: Blog posts, guides, tutorials, videos
  • ~80% of all searches are informational3

2. Navigational Intent The user wants to find a specific website or page.

  • Examples: “facebook login”, “ahrefs pricing”, “gmail”
  • Content type: Homepage, product pages, login pages
  • You can only rank if you’re the brand they’re looking for

3. Commercial Investigation The user is researching before making a purchase.

  • Examples: “best crm software”, “iphone vs android”, “ahrefs review”
  • Content type: Comparison pages, reviews, “best of” lists
  • High value for affiliate and SaaS businesses

4. Transactional Intent The user wants to complete a specific action (usually purchase).

  • Examples: “buy running shoes”, “netflix subscription”, “hire web developer”
  • Content type: Product pages, service pages, pricing pages
  • Highest conversion potential

How to Determine Intent

  1. Google the keyword - See what currently ranks. Google has tested billions of searches and knows what users want.
  2. Look at SERP features - Featured snippets suggest informational intent. Shopping results suggest transactional.
  3. Analyze the language - “How to” = informational. “Best” = commercial. “Buy” = transactional.

Keyword Metrics Explained

Search Volume

Search volume is the estimated number of searches per month for a keyword. Sources include:

  • Google Keyword Planner - Free, but shows ranges unless you’re running ads
  • Third-party tools (Ahrefs, Semrush, Moz) - Use clickstream data and Google data

Important caveats:

  • Volumes are estimates, not exact numbers
  • Seasonality affects many keywords
  • High volume doesn’t always mean high traffic potential

Keyword Difficulty

Keyword Difficulty (KD) estimates how hard it is to rank in the top 10 results. Different tools calculate this differently:

  • Ahrefs - Based primarily on backlinks to top-ranking pages4
  • Semrush - Uses multiple factors including authority and content
  • Moz - Based on Page Authority and Domain Authority of results

Scale (Ahrefs):

  • 0-10: Easy - New sites can rank
  • 11-30: Medium - Requires some backlinks
  • 31-70: Hard - Requires significant authority
  • 71-100: Very Hard - Only established sites rank

Click-Through Rate (CTR) and Traffic Potential

Not all searches result in clicks. According to a study by SparkToro analyzing 1.4 billion searches:5

  • ~65% of Google searches result in zero clicks
  • Featured snippets, knowledge panels, and other SERP features often answer queries directly

Check “Clicks” data in Ahrefs or look at actual traffic to ranking pages, not just search volume.

Cost Per Click (CPC)

CPC from Google Ads indicates commercial value. Higher CPC suggests:

  • Advertisers are willing to pay for this traffic
  • The keyword likely has conversion potential
  • Competition may be fierce

Keyword Research Process

Step 1: Seed Keywords

Start with broad topics relevant to your business:

  1. Brainstorm - What problems do you solve? What do you offer?
  2. Competitor analysis - What keywords do competitors rank for?
  3. Customer language - How do customers describe their problems?
  4. Google Suggest - Start typing and see autocomplete suggestions
  5. Related searches - Check “People also ask” and “Related searches” in Google

Step 2: Expand Your List

Use tools to find related keywords:

Free Tools:

  • Google Keyword Planner (requires Google Ads account)
  • Google Search Console (shows what you already rank for)
  • AnswerThePublic (question-based keywords)
  • Google Trends (compare popularity over time)

Paid Tools:

  • Ahrefs Keywords Explorer
  • Semrush Keyword Magic Tool
  • Moz Keyword Explorer

Expansion methods:

  • Related keywords - Semantically similar terms
  • Questions - “How”, “what”, “why” queries
  • Modifiers - Add “best”, “top”, “guide”, “2025”, etc.
  • Long-tail variations - More specific versions

Step 3: Analyze and Filter

Evaluate keywords based on:

  1. Relevance - Does this match your business and expertise?
  2. Intent match - Can you create content that satisfies this intent?
  3. Difficulty - Can you realistically rank? (Consider your domain authority)
  4. Traffic potential - Will ranking actually drive traffic?
  5. Business value - Will this traffic help your business?

Step 4: Prioritize

Create a prioritization framework:

PriorityCriteria
HighRelevant + Achievable difficulty + High traffic + High business value
MediumRelevant + Moderate difficulty + Medium traffic
LowRelevant but very competitive or low traffic
SkipIrrelevant or impossible to rank for

Long-Tail Keywords

Long-tail keywords are longer, more specific phrases with lower search volume but often higher conversion rates.

The Long-Tail Distribution

According to Ahrefs’ analysis of 1.9 billion keywords:6

  • 92.42% of all keywords get 10 or fewer searches per month
  • 0.0008% of keywords get more than 100,000 searches monthly

This means the vast majority of search traffic comes from long-tail queries.

Benefits of Long-Tail Keywords

  1. Less competition - Easier to rank for
  2. Higher conversion - More specific intent
  3. Better content match - Easier to satisfy the exact query
  4. Cumulative traffic - Many small keywords add up

Examples

Head TermLong-Tail Variation
”coffee""best coffee beans for cold brew at home"
"crm software""crm software for small real estate teams"
"python""python tutorial for data science beginners”

Competitor Keyword Analysis

Your competitors have already done keyword research. Learn from them.

How to Analyze Competitors

  1. Identify competitors - Who ranks for your target keywords?
  2. Use SEO tools to see their organic keywords:
    • Ahrefs: Site Explorer > Organic keywords
    • Semrush: Domain Overview > Organic Research
  3. Find content gaps - Keywords they rank for that you don’t
  4. Analyze top pages - What content drives their traffic?

Content Gap Analysis

Find keywords where competitors rank but you don’t:

  1. Enter your domain and 2-3 competitors in a content gap tool
  2. Filter for keywords where all competitors rank but you don’t
  3. Prioritize based on relevance and difficulty

Topic Clusters and Keyword Mapping

Modern SEO uses topic clusters to build topical authority.7

Topic Cluster Model

  • Pillar page - Comprehensive guide on broad topic (e.g., “SEO Guide”)
  • Cluster content - Detailed articles on subtopics (e.g., “Technical SEO”, “Link Building”)
  • Internal links - Connect cluster pages to pillar and each other

Keyword Mapping

Assign keywords to specific pages to avoid cannibalization:

URLPrimary KeywordSecondary Keywords
/seo-guide/seo guidesearch engine optimization, seo basics
/technical-seo/technical seotechnical seo checklist, crawlability
/link-building/link buildinghow to get backlinks, link building strategies

Rules:

  • One primary keyword per page
  • Don’t target the same primary keyword on multiple pages
  • Related/secondary keywords can overlap

Keyword Research for Different Goals

For New Websites

Focus on:

  • Long-tail keywords with low difficulty
  • Specific, niche topics where you have expertise
  • Questions (often less competitive)
  • Local keywords if applicable

Avoid:

  • High-difficulty head terms
  • Keywords dominated by major brands
  • YMYL topics (health, finance) without credentials

For E-commerce

Focus on:

  • Product category keywords (“running shoes”)
  • Product-specific keywords (“nike pegasus 40 review”)
  • Comparison keywords (“nike vs adidas running shoes”)
  • Problem-solution keywords (“shoes for flat feet”)

For B2B/SaaS

Focus on:

  • Problem-aware keywords (“how to manage remote team”)
  • Solution-aware keywords (“project management software”)
  • Comparison keywords (“asana vs monday”)
  • Integration keywords (“slack salesforce integration”)

For Local Business

Focus on:

  • “[Service] + [location]” keywords
  • “Near me” variations
  • Local landmarks or neighborhoods
  • Service-specific terms locals use

Common Keyword Research Mistakes

  1. Ignoring search intent - Creating the wrong content type
  2. Chasing volume over relevance - High volume means nothing if irrelevant
  3. Ignoring difficulty - Targeting keywords you can’t rank for
  4. Keyword stuffing - Forcing keywords unnaturally into content
  5. Not updating research - Search behavior changes over time
  6. Single keyword focus - Missing related terms and topics
  7. Ignoring competitors - Not learning from what works

Tools Comparison

ToolPriceBest For
Google Keyword PlannerFreeBasic volume data, ad planning
Google Search ConsoleFreeKeywords you already rank for
Ahrefs$99+/moComprehensive research, competitor analysis
Semrush$119+/moAll-in-one marketing, large keyword database
Moz$99+/moBeginners, SERP analysis
UbersuggestFree/$29+/moBudget option, basic research
AnswerThePublicFree/PaidQuestion-based keywords

Putting It Into Practice

Weekly Keyword Research Routine

  1. Check Search Console - Find new ranking opportunities
  2. Monitor competitors - See what new content they publish
  3. Review trends - Check Google Trends for your industry
  4. Update keyword map - Add new keywords, adjust priorities

Quarterly Deep Dive

  1. Full competitor analysis - Re-analyze top 3-5 competitors
  2. Content gap analysis - Find missing topics
  3. Performance review - Which keywords are actually driving traffic?
  4. Strategy adjustment - Shift focus based on results

Further Reading

References

Footnotes

  1. Google Search Central. “How Search Works - Returning useful results.” https://developers.google.com/search/docs/fundamentals/how-search-works ↩

  2. Google. “Search Quality Evaluator Guidelines.” Section 12.7 - Understanding User Intent. https://static.googleusercontent.com/media/guidelines.raterhub.com/en//searchqualityevaluatorguidelines.pdf ↩

  3. Moz. “The Beginner’s Guide to SEO - Keyword Research.” https://moz.com/beginners-guide-to-seo/keyword-research ↩

  4. Ahrefs. “Keyword Difficulty: How to Estimate Your Chances to Rank.” https://ahrefs.com/blog/keyword-difficulty/ ↩

  5. SparkToro. “Zero-Click Searches Study.” https://sparktoro.com/blog/in-2020-two-thirds-of-google-searches-ended-without-a-click/ ↩

  6. Ahrefs. “Long-tail Keywords Study.” https://ahrefs.com/blog/long-tail-keywords/ ↩

  7. HubSpot. “Topic Clusters: The Next Evolution of Content Strategy.” https://blog.hubspot.com/marketing/topic-clusters-seo ↩