Optimise Keywords for Google Ads

Getting traffic from Google Ads is straightforward. Getting profitable traffic at a sustainable cost per acquisition is where the real work begins. The difference between a campaign that breaks even and one that generates 4x return on ad spend almost always comes down to the quality of ongoing keyword optimisation.

Keyword optimisation is not a one-time setup task. It is a repeatable process of identifying what is working, cutting what is not, and gradually concentrating your budget on the terms that actually convert. This guide walks through the core levers: Quality Score, the Search Term Report, bid adjustments, and match type refinement.

Quality Score is made up of three factors. Improving all three simultaneously is the fastest path to lower CPCs and better ad positions.

What Keyword Optimisation Actually Means in Google Ads

The phrase 'optimise your keywords' is often used loosely. In the context of Google Ads, it means a specific set of actions: reviewing which keywords are generating clicks and conversions, identifying which keywords are spending money without producing results, adjusting bids to reflect the commercial value of each term, tightening or loosening match types based on what the data reveals, and regularly adding new negative keywords based on the actual queries triggering your ads.

The goal of all of these actions is the same: to move your budget towards keywords that convert at a profitable cost per acquisition and away from keywords that spend without converting. In a well-optimised account, the top 20% of keywords often generate 80% of the conversions. The work of optimisation is identifying that 20% as quickly as possible and concentrating investment in it.

The time frame matters too. New campaigns typically need 4 to 8 weeks before they accumulate enough data to optimise confidently. In the first month, Google's algorithm is learning which users are most likely to click and convert. Pausing keywords or slashing bids in the first two weeks interrupts this learning process. The best approach is to let the campaign run with broad controls in place, collect data, then begin systematic optimisation from week five or six onwards. Read our guide on choosing the right keywords to ensure your starting keyword list is strong enough to survive this learning period.

Understanding Quality Score and Why It Determines Your CPC

Quality Score is Google's 1 to 10 rating of how relevant your keyword, ad, and landing page are to each other and to the user's search query. A higher Quality Score means Google considers your ad a good match for the query. The commercial consequence is direct: a keyword with a Quality Score of 8 will often cost less per click than the same keyword with a Quality Score of 4, even if the latter advertiser is bidding more. Google's official documentation explains the calculation in full.

Quality Score is made up of three equally important sub-factors. Expected click-through rate reflects Google's prediction of how often users will click your ad compared to competing ads for the same keyword. Ad relevance measures how closely your ad copy matches the intent behind the search query. Landing page experience assesses whether your page delivers on what the ad promised, including load speed, mobile-friendliness, and content relevance.

Improving Quality Score is one of the highest-ROI optimisation tasks in Google Ads because its effects compound. A higher Quality Score lowers your CPC. A lower CPC means the same budget generates more clicks. More clicks with a good landing page means more conversions. The businesses that dominate competitive Australian markets are almost always operating at Quality Score 7 to 9, not 3 to 5.

The practical steps to improve Quality Score are: include the exact keyword in your headline 1, write ad copy that directly addresses the searcher's intent, create dedicated landing pages for each ad group rather than sending all traffic to the homepage, and ensure landing pages load in under 3 seconds on mobile devices.

How to Use the Search Term Report to Cut Waste

The Search Term Report inside Google Ads shows you the actual search queries that triggered your ads. This is different from your keyword list. Your keywords define the targeting parameters. The search terms show what users actually typed. The gap between the two is where most wasted spend lives.

To access the report, go to Keywords, then Search Terms in your Google Ads account. You will see every query that matched one of your keywords over the selected date range, along with the clicks, impressions, conversions, and cost associated with each. Filter for queries that have generated clicks but zero conversions. These are your waste candidates.

For each irrelevant term you find, add it as a negative keyword immediately. This prevents future spend on that query. Do this process weekly, not monthly. In the first 30 days of a new campaign, irrelevant queries are common, particularly if you have any Phrase or Broad Match keywords. The faster you build your negative keyword list from real search term data, the faster your cost per lead drops. Our article on choosing keywords effectively has a detailed section on negative keyword strategy.

If you notice queries that are converting but are not on your keyword list, that is equally valuable information. Add those queries as new Exact Match keywords with dedicated bids. This process, called "mining for converting queries", is how experienced account managers consistently find new profitable keywords that standard research tools miss. If you would like help with this process, book a free consultation with our team.

These before-and-after results are from the same campaign with the same budget. Optimisation, not more spend, drove the improvement.

Bid Strategy: Spend More on Winners, Less on Losers

Bid management is the process of adjusting how much you pay per click for each keyword based on its commercial performance. The principle is straightforward: bid more for keywords that convert at a profitable cost, bid less for keywords that struggle to convert or convert at an unprofitable cost.

In a new campaign, start with manual CPC bidding. This gives you full control over individual keyword bids and prevents Google's automated strategies from making expensive optimisation decisions before you have enough data. Once a campaign has accumulated at least 30 to 50 conversions, you can consider switching to a Target CPA or Target ROAS automated strategy, which uses machine learning to optimise bids in real time.

For manual bidding, review keyword performance at least weekly. Any keyword spending more than three times your target cost per acquisition without a conversion is a candidate for a significant bid reduction or pause. Any keyword converting at below half your target cost per acquisition is a candidate for a bid increase to capture more of that profitable traffic.

Device and location bid adjustments add another layer of precision. If your conversion data shows that mobile users convert at half the rate of desktop users, add a -30% to -50% mobile bid adjustment. If customers in a specific Melbourne suburb convert at twice the average rate, add a +20% to +30% location bid adjustment for that area.

Match Type Refinement: Tightening as Data Comes In

Match types should evolve as your campaign matures. In the first month, Phrase Match with a strong negative keyword list is the right default for most keywords. By month three, you will have search term data showing exactly which query variations are converting. Use that data to add the best-performing variations as Exact Match keywords with their own dedicated bids.

The process of 'mining and pinning', taking converting search terms and adding them as Exact Match keywords, is one of the most effective optimisation habits in Google Ads. It progressively tightens the campaign's targeting around proven converting queries while maintaining Phrase Match coverage for discovering new variations.

Five focused tasks across the week build a compound improvement in campaign performance over months.

Building a Weekly Optimisation Habit That Compounds Results

The accounts that consistently outperform in competitive Australian markets are not necessarily the ones with the biggest budgets. They are the ones with the most consistent review cadence. A 60-minute weekly review, focused on the right metrics, compounds into dramatic performance improvements over a 6 to 12 month period.

The routine is straightforward: Monday, review the search term report and flag irrelevant queries. Tuesday, add those queries as negatives. Wednesday, check Quality Scores for any keyword below 5 and plan copy or landing page improvements. Thursday, review bid performance and adjust bids for significant over- or under-performers. Friday, record the week's key metrics (CTR, CPC, conversions, ROAS) and compare to the prior week. At DigiFix, this weekly routine is the backbone of every managed account.

Frequently Asked Questions