It's a fact that launching a Google Ads campaign is far easier today than it was a few years ago. The system walks you through the key settings, suggests a budget, helps you choose a campaign type, and automation takes over more and more decisions. But at most that has made getting started simpler — not advertising profitably.
With webshops it's especially easy to misread the results. Traffic can grow, more orders can come in, ad-attributed revenue can climb, and everything on the Google Ads dashboard can look encouraging. That still doesn't guarantee more money stays in the business at the end of the month, because reported revenue and actual business profit are not the same thing.
Google Ads works from what we can measure and from the goals we give it. If all it sees is how much revenue each click generated, that's what it will try to maximise. Worse still, it doesn't necessarily know that one product carries a 45 percent margin and another only 12, or that certain orders cost far more to fulfil. That's why a webshop's Google Ads strategy shouldn't start with keywords or campaign settings. First you need a clear picture of how much acquiring a new order can cost, at most, while the sale still generates an acceptable profit.
How much ad spend can a single order carry?
There are terms marketers repeat ad nauseam, but let's start at the beginning. One of Google Ads' best-known performance metrics is ROAS — return on ad spend. The calculation is simple:
ROAS = revenue from ads / ad spend
If a webshop spends HUF 100,000 on advertising and the resulting orders bring in HUF 500,000 of revenue, the result is a ROAS of 5, or 500 percent. At first glance that may look like an excellent result — to some — but on its own it doesn't tell you whether the advertising was profitable.
Take a simple example. A webshop's average net cart value is HUF 30,000, of which the products' purchase cost is HUF 18,000. Payment, packaging, logistics and expected returns add another HUF 3,000 per order, leaving HUF 9,000 for marketing and the business's other costs. If we can spend that entire amount on customer acquisition, the break-even ROAS is roughly 333 percent:
30,000 / 9,000 = 3.33
If, however, we also want to keep at least HUF 3,000 of profit per order, we can only spend HUF 6,000 on acquiring a customer. In that case the required ROAS is 500 percent.
The example above shows nicely why there is no universally "good" ROAS. The same 400 percent figure can be an excellent result for one webshop, while for a merchant operating on thinner margins it may already mean a loss. That's why Google Ads' value-based bidding strategies — such as Maximize conversion value or Target ROAS — are particularly useful in e-commerce. They consider not only the number of purchases but also how much value each conversion represents.
Accurate measurement is not just a technical detail
Many webshops are already losing money in Google Ads when they start raising their ad budget too early — but why would anyone do that in the first place?
The campaign is running while purchase tracking still isn't fully reliable, the wrong value gets sent back to Google, or several systems each count the same order as a separate conversion. This is no minor technical nuisance; for a webshop, it's not enough to measure whether a purchase happened. If an HUF 8,000 and an HUF 180,000 order both show up as one conversion each, the system can't see the business difference between the two. The transaction value has to be transmitted accurately too, especially if the campaign uses value-based bidding.
Just as important is the unique transaction ID, which helps prevent the same order from being counted multiple times — for instance because the customer reloaded the confirmation page. Another common mistake is when the direct Google Ads measurement and the purchase event imported from Google Analytics 4 both count as primary conversions. That can easily make the system report more orders than actually occurred.
Measurement accuracy can also be improved with Enhanced Conversions. Using an encrypted version of data the customer provides — such as their email address — it can establish a more precise link between the ad interaction and the later purchase. All of this may seem like an analytics question at first, yet it has a direct effect on your advertising costs. An automated campaign can optimise consistently from faulty data too — it just easily heads in the wrong direction.
What does all this mean for a Sellvio webshop?
A webshop platform can take a lot of weight off the merchant's shoulders. True, it doesn't do the campaign strategy for you — it provides the technical foundation on which reliable measurement and analysis can be built.
Sellvio offers Google Analytics and Google Tag Manager integration, and through GTM several analytics and marketing measurements can be managed centrally. E-commerce event tracking is particularly important because a webshop's performance isn't revealed by the final purchase alone. Add-to-cart, checkout initiation and purchase completion together paint a much more accurate picture of where visitors drop off. You don't necessarily have to use all of these events as Google Ads optimisation goals, but for analysis they are genuinely valuable.
If, for example, your ads bring decent traffic and plenty of people add products to the cart, yet a conspicuous number of customers vanish before payment, the problem may not be with the ads at all. It may be the shipping fee, a missing payment option or the checkout itself causing the drop.
Product data is the foundation of Shopping ads
It's hard to imagine Google Ads without Google Merchant Center these days — at least where webshops are concerned. For Shopping placements and feed-based Performance Max campaigns, the product database itself becomes one of the advertising system's most important sources of information. The feed contains, among other things, the product's name, price, image, availability and identifiers. From these, Google tries to understand what the webshop sells and which searches each product may be relevant for. That's why the feed shouldn't be treated as a simple technical export — its quality directly affects ad performance.
Needless to say, an imprecise product name, a weak image, a faulty GTIN or wrong stock data can hurt results on its own, and with more serious discrepancies Merchant Center can restrict or reject the product's listing. It's especially important that the price and stock in the feed match what the customer sees on the product page.
Sellvio's Merchant Center product feed can eliminate a huge amount of manual work at this point. With hundreds or thousands of products, manually maintaining prices, stock levels and other data is no longer realistic, which makes an automated data connection essential. The platform's Google Ads-related export options also include Dynamic Feed and Page Feed support.
Performance Max or a traditional Search campaign?
No reason to panic: as a beginner it's easy to get lost among Google Ads campaign types, but the good news is that a small or mid-sized webshop rarely needs a complex campaign structure from day one. With a smaller budget, excessive segmentation can even be counterproductive, because each campaign has less data to learn from.
For a product-selling webshop, a common starting point is a Performance Max campaign connected to Merchant Center. It can appear across multiple Google surfaces while automating a large share of the bidding, targeting and, in part, creative decisions.
That doesn't mean, however, that traditional Search campaigns have lost their role. Someone searching specifically for "Bosch GSR 18V-55 cordless drill driver" shows a very different purchase intent from someone browsing cordless tools in general. Handling such precise searches separately still works well for many webshops. The same goes for searches on your brand name. Someone who types your webshop's name straight into Google is typically closer to buying, so this traffic shouldn't be automatically blended with the results of campaigns built to win new prospects.
Not every product is an equally good advertising target
There's a basic thesis that a ROAS calculated across the entire webshop easily hides the real differences between product categories. One group might deliver a 40–45 percent margin, low return rates and customers who come back later, while another category offers only 10–15 percent contribution, fierce price competition and higher logistics or warranty costs.
You absolutely have to watch the numbers closely, because judged by revenue alone the two categories can appear to carry the same value. As data accumulates, it's therefore worth aligning your campaign structure ever more closely with the business differences. That can be done with separate campaigns, different target ROAS values or, in some cases, conversion value rules.
Larger webshops can go even further and, alongside revenue, factor in the expected order value, the value of a new customer or even longer-term customer lifetime value. That's a more advanced approach, but the underlying principle is simple: the product worth advertising hardest isn't necessarily the one bringing in the most revenue.
A higher ROAS isn't always better
Suppose we spend HUF 100,000 a month on one campaign and it generates HUF 800,000 in revenue. That's an 800 percent ROAS. Another campaign turns HUF 1 million of spend into HUF 5 million — "only" a 500 percent ROAS.
Looking purely at the percentage, the first campaign seems better. From a business perspective, though, the second may well produce more margin and more profit.
We like to point out that a ROAS target set too high can stifle growth. If you only let the system spend at a very high return, it can compete in fewer auctions — so the ROAS stays impressively pretty while the webshop generates less profit overall. The real question, then, is at what spend level and what return the webshop produces the most profit.
Give the campaign time
Many don't like to hear it, but one of the most common mistakes in managing Google Ads is intervening too often. If the target ROAS, the daily budget, the product range or the campaign structure changes every few days, it's hard to tell which modification actually had what effect on the results.
Automated bidding needs time and a sufficient amount of data. That doesn't mean, of course, that a faulty conversion setup, a bad product feed or a technical problem should be left untouched for weeks. Those must be fixed immediately — judging the campaign's effectiveness is a different matter. On top of that, because of conversion lag, the ad spend often already appears in the statistics while a portion of the resulting purchases only happens days later. With more expensive or complex products this is even more pronounced, since customers rarely decide after a single visit — so campaigns should be evaluated over longer periods rather than on any single day's performance.
Google Ads performance is partly decided inside your webshop
The ad's job is to bring the interested visitor to your webshop, but a large part of the sale is decided the moment the ad is seen. The best quality traffic is wasted if the webshop can't convince the visitor that it's worth buying.
Take two webshops that each pay an average of HUF 180 for the same click. One converts one buyer out of a hundred visitors, the other three. The first ends up with roughly HUF 18,000 of ad cost per order, the second with just HUF 6,000. The price of the click is identical — the difference comes from the webshop's conversion performance. Precisely because of examples like this, optimising Google Ads isn't only about watching campaign settings. Product pages, shipping information, payment options and the checkout itself are just as important; a thin product description, a shipping cost revealed too late or a clunky mobile purchase flow can hurt your return more than a few percentage points of difference in the cost per click.
From this standpoint, Sellvio is not merely a surface for displaying products. The Merchant Center, Analytics and Tag Manager connections provide the technical backbone for measurement and the advertising system, while the payment, shipping, product management and checkout features shape what happens to the visitor after the click.
How should you get started?
With a new webshop the goal isn't to exploit every Google Ads feature in the first week. Far more important is a simple, transparent setup that shows you, with reliable data, what works and what doesn't. Before launching, calculate the true margin on an average order, then derive from it the customer acquisition cost your business can still bear. After that come accurate purchase value tracking, properly connecting Google Analytics with Google Ads, and checking the Merchant Center feed.
In the beginning, keep the campaign structure simple, without any overengineering. Once enough traffic and conversions have accumulated, the data will show much more clearly which product categories deserve separate handling, where spend can be increased, and at which points the problem lies not with the advertising but with the webshop itself.
The biggest mistake usually isn't caused by someone not knowing every Google Ads setting. It's trying to optimise without having precisely defined what business result the advertising is supposed to achieve.
We're not buying clicks
The Google Ads interface is all clicks, impressions, conversions and assorted ratios. It's easy to get lost in these metrics while the real goal fades into the background: a webshop doesn't need more clicks — it needs more customers it can acquire economically.
What exactly that means varies from business to business. Some operate profitably at around 300 percent ROAS, while for others the return is already inadequate below 700–800 percent. Nor is it necessarily a problem if the first order generates no profit on its own, provided the share of returning customers is high and the longer-term value of a customer can be estimated reliably.
What matters is that these decisions are made from real numbers, not gut feeling. If the measurement is accurate, the product feed is sound, you know your margins, and Google Ads is genuinely fed back the values that matter to your business, automation becomes far more effective too.
From that point on, Google Ads is no longer just a monthly ad budget you hope will bring orders — it becomes a sales channel where you can continuously see how much you invested, what result it delivered, and up to what point it's worth increasing the spend.