Semrush costs £100 per month. Ahrefs costs £100 per month. For a new website owner or small business doing their own SEO, these are significant expenses that are hard to justify before you are seeing any return. The good news: Google provides the most accurate keyword data in the world for free — you just need to know where to look and how to use it.

Quick Answer: Free keyword research uses Google Autocomplete (type your seed topic and collect suggestions), Google's People Also Ask boxes (expand them three rounds for 20–30 questions), Google Keyword Planner (free with any Google Ads account, no spend needed), and Google Search Console (shows keywords you already rank for). Together these sources provide enough data to build a comprehensive keyword strategy for any niche.

Step 1: Start with Google Autocomplete — your first free keyword source

Google Autocomplete shows you the most commonly searched completions of any phrase. These are confirmed real searches, not estimates.

  1. Open an incognito browser window (removes personalisation)
  2. Type your main topic keyword followed by a space: "SEO "
  3. Write down every autocomplete suggestion that appears
  4. Now type your keyword with letters after it: "SEO a", "SEO b", "SEO c" — new suggestions appear for each letter
  5. Try adding question starters before your keyword: "how to SEO", "what is SEO", "why does SEO"
  6. Try adding modifiers after: "SEO for beginners", "SEO for free", "SEO without tools"

In 30 minutes of systematic autocomplete mining, you can collect 50–100 confirmed keyword phrases.

Step 2: Mine Google's People Also Ask boxes for question keywords

PAA boxes are Google's direct signal of what questions people ask about your topic — and they make excellent keyword targets because they often have lower competition than statement-format keywords.

  1. Search your primary keyword
  2. Scroll to the PAA box and write down every question shown
  3. Click one question to expand it — three or four new questions appear
  4. Click those — more questions appear
  5. Repeat for three rounds

From a single seed keyword, three rounds of PAA expansion typically yields 20–35 specific question keywords. Each one is a confirmed real question with clear search intent.

Step 3: Use Google Keyword Planner to validate volume (free)

Google Keyword Planner is completely free. You need a Google Ads account but you do not need to run any ads or spend any money.

  1. Go to ads.google.com and create a free account (or use an existing one)
  2. Go to Tools → Keyword Planner → Discover new keywords
  3. Paste in your list of keywords from Steps 1 and 2
  4. Set location to your target country
  5. Click Get Results

Keyword Planner shows monthly search volume ranges for every keyword. Ranges rather than exact numbers, but accurate enough to prioritise your list — keywords showing 1,000–10,000 monthly searches have meaningfully more demand than those showing 10–100.

How accurate is Google Keyword Planner compared to paid tools?

Keyword Planner uses Google's own search data — it is the most accurate volume source available. Paid tools like Ahrefs and Semrush estimate volumes from their own data and are sometimes significantly off. For volume validation, Keyword Planner is as reliable as any paid tool.

Step 4: Use Search Console to find keywords you already rank for

If your site has been live for more than a month, Search Console is your most valuable free keyword source — because it shows real keywords your real site actually appears for.

  1. Open Google Search Console → Performance → Queries
  2. Sort by Impressions descending
  3. Download the full query list

This list shows every keyword your site appeared for in the last 16 months. Filter for queries where your average position is between 8–20 — these are near-page-one keywords where content improvements can produce fast ranking improvements without targeting any new keywords at all.

Step 5: Use Google's Related Searches for additional discovery

At the bottom of every Google search results page is a "Related Searches" section showing eight to ten additional queries related to what you searched. These are confirmed common searches in the same topic area.

Search your primary keyword, collect the related searches, then search each of those and collect their related searches. Two rounds of this generates a significant additional keyword list of related topics you may have missed.

Step 6: Analyse your competitors' content for topic gaps

Search your target keyword and look at the top three ranking pages. Note every topic and subtopic they cover — these are keywords they are targeting within a single article. Also use our Wayback URL extractor to pull a full content inventory from competitor domains and identify topics you are missing entirely.

Step 7: Prioritise your keyword list without paid tools

From your combined research, sort keywords into three groups:

  • Target now — medium volume (100–1,000 monthly searches), question format or long-tail, top results show small sites
  • Target later — higher volume but more competitive, achievable once you have some authority built
  • Monitor — keywords you appear for in Search Console at positions 8–20 that need content improvement rather than new articles

Summary: Free keyword research step by step

  • Step 1: Google Autocomplete — mine seed keyword with every letter and question starter
  • Step 2: PAA boxes — expand three rounds per seed keyword for 20–35 question keywords
  • Step 3: Google Keyword Planner — validate volume for free, no ad spend required
  • Step 4: Search Console Queries — find near-page-one keywords already on your site
  • Step 5: Related Searches — two rounds of discovery from bottom of search results
  • Step 6: Competitor content inventory via our Wayback extractor
  • Step 7: Sort into target now, target later, and monitor groups

Continue reading: How do I rank for local searches when I'm a new business?