PPC Keyword Research: How to Find the Right Google Ads Keywords Without Wasting Your Budget

Keyword research is the single most consequential decision you make when setting up a Google Ads campaign. Choose the right keywords and your budget attracts people who are actively ready to buy. Choose the wrong ones and you pay for clicks from people who would never have become customers — students doing research, competitors checking your ads, or people in completely different buying situations.

The difference between good and bad keyword strategy is often not obvious from inside the campaign. Both sets of keywords can generate clicks and even some enquiries. The gap shows up in your Cost Per Acquisition over time. Businesses with strong keyword discipline consistently pay 30–50% less per lead than those running undifferentiated broad keyword campaigns.

This guide is specifically about PPC keyword research — choosing keywords for paid search — which is distinct from SEO keyword research. In SEO, you are choosing topics to build authority around over months. In PPC, you are choosing which searches to buy right now, and the cost of getting it wrong is immediate and measurable.

Start with Intent, Not Volume

The temptation in keyword research is to pursue the highest-volume keywords first. Resist it. A keyword with 10,000 monthly searches is only valuable if the people searching it are in a position to buy from you. Moz's Search Intent Framework categorises all searches into four intent types:

• Informational: "How does a hot water system work?" — Not ready to buy.
• Navigational: "Reece Plumbing supplies Sydney" — Looking for a specific brand.
• Commercial: "Best plumber in Parramatta" — Comparing options, nearly ready.
• Transactional: "Emergency plumber Parramatta open now" — Ready to act immediately.

For most small business Google Ads campaigns, commercial and transactional intent keywords are where your budget belongs. Informational keywords generate clicks from people who are not yet buyers — you may want to create blog content for those terms, but you should not be paying for those clicks.

The Four-Step Keyword Research Process

Step 1 — Brain Dump Your Seed Keywords

Start with the simplest version of how your customers describe what they need. For a tiler in Melbourne: "tiler Melbourne," "bathroom tiling Melbourne," "floor tiling quote." Write every variation you can think of, including common misspellings, suburb variations, and service sub-types. Do not filter yet — just generate.

Step 2 — Use Google Keyword Planner to Expand and Validate

Google's Keyword Planner is free and directly shows Australian search volumes and estimated CPCs for any keyword. Enter your seed keywords and let it generate related terms. Look for keywords that combine reasonable search volume with commercial intent. Also note the average CPC — this tells you how competitive the keyword is and helps you model your likely budget requirement. Our full guide to Google Ads budgeting shows you how to use CPC data to model your campaign cost.

Step 3 — Mine Competitor Keywords

Google's Auction Insights (available once your campaign is live) and free tools like Ubersuggest show you which keywords your competitors are bidding on. This serves two purposes: discovering keywords you had not considered, and identifying gaps where competitors are spending heavily on terms that may not actually convert well — gaps you can avoid.

Step 4 — Qualify with Search Term Data Over Time

Once your campaign is live, your Search Terms Report is the most valuable keyword research document you have. It shows exactly what people typed when they saw and clicked your ad. Review this weekly. Keywords that generate clicks but no conversions become negatives. Patterns in converting searches reveal new positive keywords to add. This ongoing refinement is the discipline that separates profitable campaigns from expensive ones — and it is the core habit in the 20-Minute Weekly Audit.

Understanding Match Types: Your Most Important Technical Decision

Match types control how closely a search query needs to match your keyword before your ad is shown. Getting this wrong accounts for more wasted spend than almost any other campaign decision.

• Exact Match [keyword]: Your ad only shows when someone searches your exact keyword (or very close variants). Most controlled, lowest volume, most predictable cost.
• Phrase Match "keyword": Your ad shows when your keyword appears as part of a longer search. Moderate control, good for capturing variations.
• Broad Match keyword: Your ad can show for searches Google deems relevant — which is now very broadly interpreted. High volume, highest risk, requires strong negative keyword management.

Our recommendation for small businesses: start with Exact and Phrase match only. Add Broad Match only after you have 60+ days of Search Term data and strong negative keyword lists in place. This matches the approach taught in our Google Ads 2026 Blueprint.

Building Your Negative Keyword List

Negative keywords are terms you explicitly tell Google not to show your ad for. They are as important as your positive keywords — perhaps more so, because they protect your budget from irrelevant clicks. Common negative keyword categories for Australian small businesses:

• DIY terms: "how to," "do it yourself," "tutorial," "free"
• Employment terms: "jobs," "careers," "salary," "apprenticeship"
• Wholesale/trade: "wholesale," "bulk," "trade price"
• Competitors: Add competitor brand names if you do not want to show for brand-specific searches
• Geographic exclusions: Suburbs or cities you do not service

According to WordStream's analysis of Google Ads campaigns, accounts with active negative keyword management achieve 30–40% lower CPCs than comparable accounts without negative lists. It is the most cost-effective improvement available to any campaign already running.

Organising Keywords into Ad Groups

Keywords should be grouped into tightly themed Ad Groups where every keyword relates to the same specific service or topic. This allows you to write ad copy that directly matches the search — which improves your Quality Score, reduces your CPC, and increases your conversion rate.

A common mistake is putting all keywords in one Ad Group and writing one generic ad. A plumber should have separate Ad Groups for "blocked drains," "hot water systems," "bathroom renovation," and "emergency plumbing" — each with ads written specifically for that service and linking to a page about that specific service. The more tightly matched the keyword, ad, and landing page, the more Google rewards you.

Good keyword research is not about finding the most searches. It is about finding the searches where someone is ready to buy what you sell, in the area you serve, right now.