How to Choose the Right Keywords for Google Ads
Key Takeaways
- The wrong keywords will drain your budget on irrelevant traffic regardless of how well everything else is set up
- Google Ads offers four match types: Broad, Phrase, Exact, and Negative, each controlling how closely queries must match
- Search intent (informational, commercial, transactional) determines whether a keyword will actually convert into a lead
- Negative keywords are as important as positive ones and should be built before launch, not after
- Keyword selection is a research process, not a guessing exercise, and the right tools make it faster and more accurate
Most Google Ads campaigns do not fail because the ads were badly written or the budget was too small. They fail because the wrong keywords were chosen from the start. No amount of great ad copy can save a campaign pointed at the wrong search terms. Keyword selection is the single most consequential decision you make in any PPC campaign.
Choosing the right keywords means understanding how your potential customers think when they search, what stage of the buying journey they are in, and what match type gives you the right balance of reach and relevance. This guide walks you through the process from start to finish.
The four match types control who sees your ad. Getting this wrong is the fastest way to waste your budget.
Why Keywords Are the Single Most Important Decision in Any Campaign
Think of keywords as the targeting coordinates for your campaign. A sniper with the right coordinates hits the target every time. The same sniper with the wrong coordinates fires all day and hits nothing. Budget, bidding strategy, and ad copy quality are all secondary to whether you are targeting the right search queries in the first place.
Google Ads works by matching your chosen keywords to what real users type into the search bar. Every time someone's query matches one of your keywords, you enter an auction. If you win the auction, your ad shows. If the user clicks, you pay. The question is: who are you putting your ad in front of? That is determined entirely by the keywords you choose.
This matters beyond campaign efficiency. Keyword choice also directly affects your Quality Score. A keyword that closely matches the intent behind a query earns a higher relevance score, which lowers your cost per click and improves your ad position. Choosing keywords that are too broad or too vague increases your costs while decreasing the quality of traffic you receive.
The other dimension is competitive cost. In Australian markets, highly competitive keywords like "personal injury lawyer Melbourne" or "mortgage broker Sydney" attract dozens of advertisers and can cost $30 to $80 per click. Narrower, more specific keywords like "conveyancing lawyer Melbourne CBD" may deliver fewer searches but at a fraction of the cost and with higher purchase intent.
Understanding the Four Google Ads Match Types
Every keyword in Google Ads has a match type attached to it. Match type controls how closely a user's search query must resemble your keyword before your ad is eligible to show. This is one of the most misunderstood settings in the platform, and getting it wrong is the root cause of most wasted ad spend.
| Match Type | How It Works | Best Use Case | Risk Level |
|---|---|---|---|
| Broad Match | Ads show for synonyms, related searches, and Google's interpretation of intent | Discovery campaigns only, with careful negative keyword management | High |
| Phrase Match | Ads show when search contains your phrase in order, with words before/after allowed | Balanced targeting when you have some data about how customers search | Medium |
| Exact Match | Ads show only for exact keyword or very close variants | High-intent keywords proven to convert | Low |
| Negative Keywords | Blocks specified terms from triggering your ad | Filtering irrelevant traffic across all match types | N/A |
Start with Phrase and Exact match for a new campaign. Add Broad Match only after you have conversion data to guide it.
For most new campaigns in Australia, the safest starting point is Phrase Match for discovery and Exact Match for your highest-intent keywords. Avoid Broad Match until your campaign has at least 30 days of data and you have a strong negative keyword list in place. Our article on optimising keywords for Google Ads covers how to tighten match types as data comes in.
Search Intent: Why Not All Keywords Are Equal
Two people searching for related terms can have completely different intentions. One might be researching to learn. Another might have their credit card in hand. Targeting both keywords with the same ad spend makes no sense if only one of them is likely to call you.
Search intent falls into three categories. Informational intent covers queries like 'how does PPC work' or 'what is a Quality Score'. These searchers are learning, not buying. Commercial intent covers queries like 'best Google Ads agency Melbourne' or 'Google Ads vs SEO comparison'. These searchers are evaluating options. Transactional intent covers queries like 'hire Google Ads specialist' or 'Google Ads management Melbourne'. These searchers are ready to act.
For most service businesses in Australia, transactional keywords should receive your highest bids. Commercial keywords are worth targeting at moderate bids, particularly for retargeting. Informational keywords are generally not worth bidding on in a direct response campaign, though they can form the basis of a brand awareness strategy. If you are unsure which intent category a keyword falls into, book a free consultation and we will walk you through it for your specific industry.
Not sure which keywords your customers are actually using?
Book a free strategy call with Nel. We will show you exactly what your ideal customers are searching for in Melbourne and give you a keyword list you can use immediately.
Book your free consultation
Search intent determines whether a keyword will convert. Transactional keywords are your money terms.
How to Build Your First Keyword List in Four Steps
Building a keyword list is a research exercise, not a brainstorming session. The goal is to find the phrases your actual customers type, not the phrases you think sound right. Here is a repeatable four-step process.
Step 1: Think like your customer, not like your business. Write down 10 to 15 phrases a customer would type when they need your service and do not know your company name. Think about symptoms and problems, not your service category. "Office roof leaking" will often outperform "commercial roofing services" because it matches the moment of urgent need.
Step 2: Run your seed phrases through Google Keyword Planner. This free tool inside Google Ads shows you search volumes, competition levels, and suggested bids for Australia. It also generates keyword variations you may not have considered. Filter for keywords with at least 50 monthly searches in your target location.
Step 3: Check competitor ads. Search for your top keywords in an incognito browser window and note which competitors are running ads. Their ad copy often reveals which angles and benefits resonate with your shared audience. You can also use Ahrefs or SEMrush to see the exact keywords competitors bid on.
Step 4: Filter ruthlessly. Remove anything that is informational only. Remove anything with ambiguous intent. Keep only the keywords where you are confident a clicking user is close to making a decision. Quality beats quantity every time in Google Ads.
Negative Keywords: The Feature Most Advertisers Ignore
Negative keywords are terms you tell Google to never match your ads against. They are, without exaggeration, the most cost-effective optimisation you can make to any Google Ads campaign. Yet a significant proportion of Australian small business accounts have either an empty negative keyword list or one with fewer than 10 terms.
Before launching any campaign, build a starter negative list covering at minimum: intent signals you do not want ('free', 'cheap', 'DIY', 'how to', 'tutorial', 'course', 'training'), employment searches ('jobs', 'careers', 'salary', 'vacancy', 'internship'), and product or service categories adjacent to yours but not relevant to your offer.
Add to this list weekly using the Search Term Report inside Google Ads. This report shows you the actual queries that triggered your ads. Every irrelevant term you find goes straight onto your negative keyword list. This process alone can cut wasted spend by 20 to 40% within the first month.
Follow this five-step process every time you build a new campaign. It replaces guesswork with research.
How DigiFix Builds Keyword Strategies for Melbourne Clients
When DigiFix takes on a new Google Ads client, keyword research is the first two weeks of work. We start with a deep audit of the client's existing search term data (if they have prior campaigns), combine it with competitor keyword intelligence from Ahrefs and SEMrush, and validate everything against Google Keyword Planner data for Australian search volumes.
The output is a tiered keyword list: primary high-intent terms for Exact Match at maximum bids, secondary commercial terms for Phrase Match, and a comprehensive negative keyword list ready before launch. No guesswork. No broad match keywords in the first 60 days. Every keyword earns its place with real data. See our full approach on the digital marketing services page.
Want a keyword strategy built on real data, not guesses?
Book a free 30-minute consultation with Nel. We will show you exactly which keywords your customers are using in Melbourne and give you a clear plan to target them profitably. No obligation, no hard sell.
Book your free consultation