Google Ads is not a difficult platform to use. It is a very difficult platform to use well. The interface is designed to make spending easy and make performance visible — but the numbers it shows you by default are not always the ones you should be looking at.
This matters because Google Ads is one of the most common places where small businesses lose money slowly. Not in big, obvious chunks — but in small, steady leaks. A broad match keyword pulling in irrelevant searches. A campaign spending most of its budget by 10am and going dark for the rest of the day. A landing page that's receiving clicks but converting no one. Each of these problems has a clear signal in the data. Most people never look for it.
This guide covers Google Ads specifically. If you haven't read Guide #2 (How to know which marketing channel is actually driving revenue), it's worth starting there — it explains how Google Ads fits into your overall attribution picture and why the conversion numbers inside Google Ads and GA4 often tell different stories.
A quick note before we start: this guide assumes you are running Search campaigns — ads that appear when someone types a query into Google. Display campaigns (ads that appear on websites), Shopping campaigns, and Performance Max campaigns each have their own performance logic and will be covered in later guides.
What this guide covers and what it doesn't: This guide focuses on Google Search campaigns — the ads that appear at the top of Google when someone searches for something. Display, Shopping, YouTube, and Performance Max campaigns behave differently and are not covered here. If you're running those campaign types alongside Search, apply the principles in this guide to your Search campaigns and look out for dedicated guides on the others later in this series.
When you first open Google Ads, the default view shows you a summary of your account: impressions, clicks, click-through rate, average cost per click, conversions, and cost per conversion. This is a reasonable starting point — but there are two things to know before you trust any of it.
First: Google Ads uses its own attribution model by default. As covered in Guide #2, Google Ads reports conversions using last-click attribution across a 30-day window — meaning if someone clicked your ad and then converted any time in the next 30 days, even via a different channel, Google Ads counts that conversion. This tends to make Google Ads look more effective than it is when compared to GA4, which counts the session that immediately preceded the conversion. Neither is wrong — they're measuring different things. But when reviewing Google Ads performance, always cross-reference with GA4 before drawing conclusions.
Second: the default date range is often misleading. Google Ads defaults to the last 30 days. If you changed a campaign setting, a bid, or a budget in the middle of that window, you're looking at blended performance from two different configurations. Always check when you last made significant changes and set your date range accordingly.
What to look at versus what to ignore:
The Recommendations tab — Google's built-in suggestions for how to improve your campaigns — should be treated with caution. Most recommendations are designed to increase spend, not improve efficiency. "Add more keywords," "enable broad match," and "increase your budget" are among the most common. Some recommendations are genuinely useful. Most are not. Never apply a recommendation without understanding what it will do.
The Auction insights report, by contrast, is one of the most underused features in the platform. It shows you who else is bidding on the same searches as you, how often their ads appear compared to yours, and where your ads appear on the page relative to competitors. This context is essential for understanding why your performance changes when you haven't changed anything yourself.
The recommendations trap: Google Ads' Recommendations tab has an "Optimization score" — a percentage showing how closely your account follows Google's suggestions. A low score looks alarming. It isn't. The optimization score is a measure of how much you've done what Google recommends, not how well your campaigns are actually performing. Applying recommendations to chase a higher score, without evaluating each one critically, is one of the most reliable ways to increase spend without improving results.
You don't need to read every report in Google Ads. You need to read five of them, consistently, every week. Here's where to find each one and what to look for.
1
Search terms report
This is the most important report in Google Ads and the one most people never look at.
Your keywords are what you tell Google to bid on. Your search terms are what people actually typed before they saw your ad. These two things are not the same.
If you're bidding on the keyword "project management software," Google might also show your ad to people who searched "free project management templates," "project management jobs," or "project management course." Depending on your match type settings (covered in section 4), the gap between what you're bidding on and what you're actually showing up for can be enormous — and expensive.
Where to find it: Google Ads → Campaigns → [select a campaign] → Keywords → Search terms.
What to look for: Read through the list of actual search terms. For each one ask: is this the kind of query someone who might buy from me would type? If the answer is no, add it as a negative keyword (an instruction to Google not to show your ad for that term). This is one of the highest-value actions you can take in Google Ads and it costs nothing.
2
Campaign performance by time of day and day of week
Not all hours and days perform equally. Your campaigns might be spending 60% of their budget between 8am and 11am, reaching people at their desks before a working day starts — but your customers might actually convert most often at lunchtime or in the evening. Understanding when your ads perform best lets you bid more aggressively during high-performing times and less aggressively during low-performing ones.
Where to find it: Google Ads → Campaigns → select campaign → Segments → Time → Day of week or Hour of day.
What to look for: Compare cost per conversion by hour and by day. If certain hours are consistently producing conversions at half the cost of others, you should be bidding up during those hours. If certain hours are producing clicks but zero conversions, consider reducing your bid or pausing ads entirely during those windows.
3
Keyword performance
our keywords tab shows you how each keyword in your account is performing individually — impressions, clicks, click-through rate, cost per click, conversions, and cost per conversion.
Where to find it: Google Ads → Campaigns → [select campaign] → Keywords.
What to look for: Three things. First, keywords with high spend and zero conversions over four or more weeks — these are candidates for pausing. Second, keywords with a high click-through rate but low conversion rate — this usually means the ad promise and the landing page experience don't match. Third, keywords with a low impression share — if your keyword has a low impression share, it means Google isn't showing your ad for all the searches where it could. This often means your bid or quality score is too low.
4
Landing page performance
Google Ads can tell you how many people clicked your ads and went to each landing page. GA4 tells you what those people did after they arrived. Together, these two reports tell you whether your landing pages are doing their job.
Where to find it: In Google Ads → Campaigns → select campaign → Ad Groups → view destination URLs. Cross-reference with GA4 → Reports → Engagement → Landing page.
What to look for: A high click-through rate on an ad combined with a high bounce rate (or low engagement rate) on the landing page means people are interested enough in the ad to click, but the page isn't delivering on the promise. This is a landing page problem, not an ads problem — and increasing your ad budget will not fix it.
5
Impression Share
Impression share is the percentage of times your ad was shown out of the total times it was eligible to be shown. An impression share of 40% means your ad appeared in 40% of the auctions it entered. The remaining 60% is either lost to budget (you ran out of daily budget) or lost to rank (your quality score or bid wasn't high enough to win the auction).
Where to find it: Google Ads → Campaigns → add the "Search impression share," "Search lost IS (budget)," and "Search lost IS (rank)" columns using the column selector.
What to look for: If you're losing impression share to budget, your campaigns are running out of money before the day ends. The fix is either increasing the budget or tightening your targeting so each click costs less. If you're losing impression share to rank, your quality score or bids need attention. Both problems represent wasted potential — auctions you could be winning but aren't.
Start with the Search terms report: If you only do one thing after reading this guide, make it this — open your Search terms report, read through the actual queries people used to find your ads, and add anything irrelevant as a negative keyword. Most Google Ads accounts accumulate months or years of wasted spend on irrelevant searches because nobody has ever done this. It takes about 20 minutes and the savings are often immediate.
Match types control how closely a search query needs to match your keyword before Google shows your ad. There are three main types. Understanding the difference between them is fundamental to controlling where your budget goes.
Exact match
Your ad only shows when someone searches for exactly the keyword you've specified, or close variants of it (plurals, misspellings, reorderings). If you're bidding on [project management software] in exact match, your ad will show for "project management software" and "project management softwares" but not for "best project management tools" or "project management app."
Exact match gives you the most control. It also gives you the lowest reach. Use it for your most commercial, highest-intent keywords — the searches where you know exactly what the person is looking for and you have a strong offer to match.
Phrase match
Your ad shows when someone searches for a phrase that contains your keyword, in the same order, with additional words before or after. If you're bidding on "project management software" in phrase match, your ad might show for "best project management software for small business" but not for "software for managing projects."
Phrase match is a reasonable balance between control and reach for most campaigns. It captures more search variations than exact match while still maintaining meaningful relevance.
Broad match
Your ad shows for any search Google considers related to your keyword — which can include synonyms, related concepts, and searches that share only a thematic connection to your keyword. If you're bidding on "project management software" in broad match, Google might show your ad to someone searching "team collaboration tools," "how to manage a project," or "project manager jobs."
Broad match gives Google maximum flexibility in deciding when to show your ads. It is also the most expensive match type to run without careful management, because without regular negative keyword work, it will show your ads for a wide range of queries that may have nothing to do with what you sell.
Google now defaults new keywords to broad match. This means many advertisers are running broad match without realising it — and wondering why their Search terms report is full of irrelevant queries.
The broad match trap: Broad match is not inherently bad — it can work well when combined with strong conversion data (so Google's algorithm knows what a good customer looks like), a healthy negative keyword list, and regular Search terms report reviews. But for accounts with limited conversion history, limited budgets, or infrequent management, broad match tends to spend aggressively on low-quality traffic. If your budget is under £2,000/month, consider starting with phrase match and exact match only until you have enough conversion data to guide Google's broad match algorithm effectively.
Quality Score is Google's rating of the quality and relevance of your keywords, ads, and landing pages. It is scored from 1 to 10 for each keyword. A higher Quality Score means Google considers your ads more relevant to the searches you're bidding on — and rewards you with lower costs and better ad positions.
This is not a minor detail. Quality Score directly affects how much you pay per click. Two advertisers bidding the same amount on the same keyword can pay very different prices — if one has a Quality Score of 8 and the other has a Quality Score of 4, the advertiser with the higher score will typically pay less per click and appear higher on the page.
Quality Score is made up of three components:
Expected click-through rate: How likely Google thinks people are to click your ad when it appears. This is based on your historical performance relative to other advertisers in the same auctions. A low expected CTR suggests your ad copy isn't compelling enough or isn't relevant enough to the search.
Ad relevance: How closely your ad copy matches the intent of the keyword. If someone searches "accountancy software for small business" and your ad says "Accounting tools for teams," Google considers that moderately relevant — the topic matches but the language and specificity don't. Writing ad copy that closely mirrors the language and intent of your keywords is one of the fastest ways to improve Quality Score.
Landing page experience: How useful and relevant Google considers your landing page for someone who clicked on the ad. Google evaluates factors like page load speed, how closely the page content matches the search query, and whether the page is easy to navigate on mobile.
Where to find it: Google Ads → Keywords → add the "Quality Score" column using the column selector. Also look at the three sub-component columns: "Exp. CTR," "Ad relevance," and "Landing page exp."
What to look for: Any keyword with a Quality Score below 5 is costing you more than it should. The sub-component columns will tell you which of the three areas is dragging the score down. Address the lowest-rated component first.
Quality Score is a diagnostic tool, not a target: Don't chase a perfect Quality Score of 10 across all keywords. Some keywords are inherently harder to match closely, and a score of 6 or 7 is fine for many campaigns. The most valuable use of Quality Score is identifying keywords where the score is significantly below average — those are the ones costing you more than they should and signalling a mismatch between your ad, your keyword, and your landing page.
This is where the reports from section 3 come together. Rather than reading each metric in isolation, you're looking for patterns across multiple signals — the same principle introduced in Guide #2 for channel attribution.
A campaign is healthy if:
Cost per conversion is stable or improving on a 4-week trend. Impression share is above 60% and not primarily being lost to budget. The Search terms report shows queries that are clearly relevant to your offer. Quality Score is 6 or above for your core keywords. Conversion volume is at or above your monthly target.
A campaign needs attention if:
Cost per conversion has increased for three or more consecutive weeks without a clear external cause (seasonality, competitor activity). Impression share lost to budget is high — meaning you're running out of money before the day ends. The Search terms report contains a significant proportion of irrelevant queries. Click-through rate is declining week after week, suggesting ad fatigue or declining relevance.
A campaign is likely wasting money if:
The Search terms report shows a pattern of irrelevant or low-intent queries over multiple weeks. There is consistent spend with zero or near-zero conversions over six or more weeks, and you've confirmed your conversion tracking is working correctly. Quality Scores are consistently below 4 for multiple keywords. Cost per conversion is more than double your target across four or more consecutive weeks.
The most common waste pattern in Google Ads is not one dramatic failure — it's many small inefficiencies running simultaneously. A broad match keyword pulling irrelevant traffic. An ad group with three ads where one is consuming 90% of impressions and converting poorly. A campaign running 24 hours a day when 80% of conversions happen between 9am and 6pm. Individually each is manageable. Together they compound into significant wasted spend.
The set-and-forget trap: Google Ads campaigns do not manage themselves. Google's automated bidding strategies improve over time with conversion data — but they also optimise toward whatever you tell them to optimise for. If your conversion tracking is misconfigured, if your budget runs out by midday, or if your Search terms report is full of irrelevant queries, Smart Bidding will optimise efficiently toward the wrong outcomes. Automation amplifies what's already happening — good and bad. The manual review work in this guide is what keeps the automation honest.
When Google Ads performance drops — cost per conversion rises, conversion volume falls, or both — the cause is almost always one of a small number of things. Work through this checklist in order before changing anything significant.
Check if something external changed
Before assuming anything is wrong with your campaigns, check what happened in the market. Did a major competitor enter the auction? (Check Auction insights.) Did search volume for your core keywords drop? (Check Google Search Console for changes in branded and non-branded search impressions.) Is there a seasonal pattern that explains the timing? The first question to answer is always: did the market change, or did my campaigns change?
Check your conversion tracking
Before attributing a drop in conversions to campaign performance, confirm that your conversion tracking is still working. A tracking script that breaks during a website update is a common cause of sudden conversion drops — the conversions are still happening, but they're not being recorded. Go to GA4 → Real-time report and complete a test conversion on your own site. Confirm it appears in the data. Then check Google Ads → Tools → Measurement → Conversions and confirm your conversion actions show recent activity.
Check the Search terms report for new irrelevant traffic
Open your Search terms report and filter to the last 14 days. Look for search queries that are new and irrelevant. A change in Google's matching behaviour, a new broad match keyword, or a budget increase can sometimes open the floodgates to irrelevant traffic. If you see a pattern of new irrelevant queries, add negatives immediately.
Check impression share and budget pacing
If impression share lost to budget has increased, your campaigns are running out of money sooner in the day — which means you're missing auctions during whatever time of day your audience is most active. This can cause conversion volume to drop without any change in campaign quality. Check your budget pacing by looking at the time-of-day performance report and confirming whether your spend is cutting off mid-afternoon.
Check for Quality Score changes
Check whether Quality Scores have dropped on your core keywords. A Quality Score drop usually means one of three things: your ad's click-through rate has declined (ad fatigue, or a competitor writing a more compelling ad), your landing page has changed in a way that reduced its relevance score, or Google has recalibrated its assessment of your expected CTR based on recent performance.
Check for bid strategy changes or automated recommendations applied
If you or anyone else applied a recommendation from Google's Recommendations tab in the last 30 days, that change may be the cause. Check your Change history: Google Ads → Tools → Change history. This shows every change made to your account, who made it, and when.
The single most important thing to do before changing anything: When performance drops, the instinct is to do something — increase budgets, change bids, rewrite ads. Resist this for at least 48–72 hours unless the drop is dramatic. Most short-term performance dips are statistical noise. The diagnostic checklist above should tell you within a week whether there is a genuine underlying problem or whether you're looking at normal variance. Changing things before you've diagnosed the cause tends to create more variables, not fewer — making the next diagnosis harder.
Managing Google Ads to the standard described in this guide requires more than checking a number once a week. It requires regular, structured attention — and the compounding benefit of that attention is significant. Accounts that are reviewed and optimised consistently outperform accounts that are set up and left alone, even when the initial setup is strong.
That's roughly 50–60 hours per year of structured Google Ads management — not counting the cognitive overhead of switching between the platform and your spreadsheet, holding historical context in your head, and making judgement calls without a clear framework.
For Google Search ads, a click-through rate of 3–5% is generally considered healthy for most industries and campaign types. Branded campaigns (where you're bidding on your own company name) often see CTRs of 10–30% because the searcher already knows who you are. Non-branded campaigns — where you're competing for searches from people who don't know you yet — typically have lower CTRs, and 2–4% is reasonable. The more important number is how your CTR compares to your own historical performance and to what Google shows as your expected CTR in the Quality Score breakdown. A CTR that's declining over four or more weeks is a signal that your ads are losing relevance or that competitors are improving.
There is no universally correct answer, but there is a useful framework. You need enough budget to generate a statistically meaningful number of conversions — ideally 30 or more per month at the campaign level — before Google's Smart Bidding algorithms have enough data to optimize effectively. If your average cost per conversion is £50 and you want 30 conversions per month, you need at least £1,500/month. Running campaigns at lower budgets than this is not necessarily wrong, but you should expect the algorithm to underperform and plan to manage bids more manually. Never set a budget you're not comfortable spending entirely in a month — Google will spend it.
CPC (cost per click) means you pay every time someone clicks your ad. CPM (cost per thousand impressions) means you pay based on how many times your ad is shown, regardless of whether anyone clicks. Google Search campaigns almost always use CPC or target CPA (where you set a target cost per conversion and Google's algorithm adjusts bids automatically). CPM bidding is more common in Display and YouTube campaigns. For Search campaigns, CPC or target CPA bidding is the right choice for most small businesses.
No. As covered in section 2 of this guide, optimization score measures how closely you've followed Google's recommendations — not how well your campaigns are performing. An account with an optimisation score of 47% can be profitable and efficient. An account with a score of 95% can be wasteful and ineffective. The only metrics that matter are cost per conversion, conversion volume, and how these trend over time relative to your target. Ignore the optimization score unless a specific recommendation within it is genuinely relevant to your situation.
There are several common causes. First, your bids may be too low to win auctions — check your impression share and how much is lost to rank. Second, your daily budget may be set too low relative to the competition for your keywords — a daily budget of £5 for highly competitive keywords may not generate a single impression. Third, your keywords may have very low search volume — Google pauses keywords that receive fewer than a certain threshold of searches. Fourth, your ads may be eligible to show only during specific hours if you've set ad scheduling. Fifth, your targeting may be very narrow — check your location, device, and audience settings. The Search impression share report will tell you whether the problem is budget or rank, which narrows down the cause significantly.
For most small businesses with enough conversion data (30 or more conversions per month per campaign), Target CPA or Target ROAS Smart Bidding generally outperforms manual CPC over time, because it can adjust bids in real time based on dozens of signals that manual bidding cannot account for. However, Smart Bidding requires enough conversion data to work effectively. If you're running a new campaign with little conversion history, start with Maximize Clicks (to gather data) or manual CPC (to maintain control) and switch to a conversion-based Smart Bidding strategy once you have sufficient data. Never switch bidding strategies mid-week — give any strategy change at least two to four weeks before evaluating performance.
A negative keyword is a search term you tell Google you don't want to trigger your ads. For example, if you sell premium accounting software and you're seeing searches for "free accounting software" in your Search terms report, adding "free" as a negative keyword tells Google not to show your ads for any search containing the word "free." To add negative keywords: Google Ads → Keywords → Negative keywords tab → click the blue plus button → add at campaign or ad group level. Campaign-level negatives apply to all ad groups within the campaign. Ad group-level negatives apply only to that specific ad group. If a term is irrelevant to your entire campaign, add it at campaign level.
The simplest check: complete a test conversion on your own site (submit a contact form, complete a purchase in test mode, click a tracked phone number) and check whether it appears in GA4's real-time report within a few minutes. Then check Google Ads → Tools → Measurement → Conversions and confirm the conversion action shows a recent "Last conversion" date. If the last conversion date is more than a week ago and you know people have been enquiring or purchasing, your tracking has likely broken. Common causes include a website update that removed the tracking script, a tag manager issue, or a form plugin that changed the page URL after submission (breaking the page-view-based conversion trigger). If you're unsure, a Google Tag Manager audit will usually identify the problem.
Google Ads management is a full-time job in a part-time world
Everything in this guide works. Regular Search terms report reviews, Quality Score monitoring, time-of-day analysis, and a clear diagnostic process when performance drops — these are the habits that separate well-managed Google Ads accounts from ones that quietly bleed budget.
The honest reality is that doing this properly takes consistent time and attention. The weekly review, the monthly deep dive, the judgement calls about when to pause and when to push — none of this is intellectually difficult. But it is relentless. And for a marketing manager running multiple channels, managing a team, and reporting to leadership, it is the kind of work that slips first when things get busy.
Zynop reads your Google Ads data every week alongside your other channel data, flags what's changed and what it means, and surfaces the specific actions most likely to improve performance — or stop the bleeding if something has gone wrong. No switching between tabs, no holding historical context in your head, no wondering whether this week's dip is signal or noise.
If you're not ready for that yet, this guide gives you what you need to manage Google Ads well manually. The next guide in this series covers Meta ads — how to read your Facebook and Instagram campaign data, what the numbers actually mean, and how to know when creative fatigue is killing your performance before it costs you.