Search engine advertising

Search engine advertising, SEA for short, means paid placements in search results and the networks attached to them. Older names such as keyword advertising or sponsored links mean the same thing. The decisive difference from every other form of advertising: you reach people at the moment they are searching for something themselves. Nobody has to be interrupted.

SEA and search engine optimisation are often set against each other, although together they make up the broader field of search engine marketing. The difference lies in timing and cost structure: an ad is visible an hour after approval and costs per click. An organic placement takes months and then costs nothing per visitor.

This page describes which campaign types exist, how the auction behind an ad calculates, what can be steered, and which work we take on.

The campaign types and what they are good for

Search campaigns are the core. Ads appear for specific search queries and are billed per click. Since 2022 the format has been exclusively the Responsive Search Ad: you supply several headlines and description texts, and Google assembles an ad from them for each auction. The earlier expanded text ads with fixed lines no longer exist. Anyone wanting to keep control over the wording works with pinned positions – though that restricts the number of combinations the system can learn from.

Shopping campaigns draw their ads from a product data feed. The quality of that feed determines success more than any setting in the account: title, product type, category, availability, GTIN.

Performance Max bundles Search, Shopping, Display, YouTube, Discover and Gmail into one campaign that Google largely steers itself. The return is often good, the insight into how it came about slight. The type only becomes sensible with clean conversion tracking, sufficient data volume and exclusions for brand queries – otherwise the campaign buys clicks on your own company name and credits itself with the success.

Demand Gen runs image and video ads across YouTube, Discover and Gmail. That is demand generation, not demand capture – expectation and measurement differ accordingly.

Display and video campaigns suit awareness and remarketing to visitors who have been there before. As the sole channel for direct sales they usually disappoint.

Alongside Google we run campaigns in Microsoft Advertising – the service formerly called Bing Ads. The market share is smaller, the click prices often are too, and the composition of the audience differs noticeably. For B2B offerings it is regularly worth a look.

Keywords, match types and the role of smart bidding

You do not book an ad against a search query but against a keyword with a matching rule. With exact match, delivery happens only on very close correspondence; with broad match, also on related formulations; phrase match sits in between. For years broad match counted as burning money, because the matching was too generous. That has shifted. In combination with automated bidding strategies, Google also evaluates context, landing page and previous conversions, and broad match finds formulations nobody thought of when the campaign was built.

Both are preconditions: a bidding strategy that optimises for conversions – target CPA, target ROAS or maximise conversions – and enough measured conversions for the system to have something to learn from. Below a certain volume per month, manual or click-based strategies are more honest.

What no account may lack is negative keywords. The search terms report shows what delivery actually happened for; without regular maintenance of that list you pay for queries that have nothing to do with your offering.

How the ad auction calculates

An auction runs for every single search query. Not once a day, not per keyword – every time anew, in the fraction of a second between input and results page.

First the system checks which ads are eligible for the query at all. For each of them an Ad Rank is formed, which takes in:

• the bid – the amount you would pay at most for a click,
• ad quality, that is expected click-through rate, relevance of the ad to the query, and the landing page experience,
• the context of the search query: location, device, time of day, further signals,
• the expected effect of ad extensions such as sitelinks, call or location details,
• thresholds meant to ensure a minimum quality.

Only that rank determines the order. A high Ad Rank from good quality beats a higher bid with poor quality – which is why accounts with a carefully built structure buy more cheaply than accounts that simply bid more.

What is then paid is generally not your own bid but the amount that was necessary to exceed the Ad Rank of the next-placed advertiser. That is why the actual click price is almost always below the maximum bid.

In the account, the quality assessment appears as Quality Score on a scale from 1 to 10, composed of expected click-through rate, ad relevance and landing page experience. A high value lowers the price you pay for the same position; a low one raises it or prevents delivery entirely. It is a diagnostic aid, not a lever: it cannot be set directly, only influenced through better ads, tighter ad groups and more suitable landing pages.

The third component is the one most accounts lose on: ads leading to the homepage instead of the matching subpage, or landing pages that build too slowly on a phone.

Billing models

CPC – cost per click. The normal case in search. You pay when someone clicks, not when the ad appears.

CPM – cost per thousand impressions. Common in display and video advertising, where visibility matters rather than the individual click.

CPV – cost per view. Billed when a video has been watched for a certain duration.

Target CPA and target ROAS are not billing models but bidding strategies: you state what a conversion is worth to you or what revenue per advertising euro you are aiming at, and the system steers the bids towards it.

Why an ad does not appear

The most common reason for questions. The usual causes:

• The daily budget is exhausted, often by mid-morning.
• Ad Rank sits below the threshold – usually a quality question, not a bid question.
• An ad breaches the advertising policies and has been disapproved.
• The search query does not fit the chosen match type, or is excluded.
• Targeting by location, language or time window does not apply.

A special case: googling your own ad generates impressions without clicks and worsens the click-through rate. The account has an ad preview tool for that.

The metrics that come out of it

Impressions show how often delivery happened. Clicks, and the click-through rate derived from them, show how convincing the ad was in the results list. The average click price shows what the market currently costs.

After that it gets more interesting. The conversion rate shows what happens after the click. Cost per conversion and revenue per advertising euro show whether the whole thing pays for itself. And impression share shows how much of the available demand you are picking up at all – if it stays low while the campaign is profitable, money is lying in the street.

One metric alone does not carry a decision. Falling click prices alongside a falling conversion rate are not a success but cheaper, worse traffic.

Measurement and consent

Without functioning conversion tracking, a campaign is an expense without feedback. What has to be measured is what counts for your business – a completed order, a submitted form, an answered call – not the click on a button.

Since March 2024 Google has required Consent Mode v2 for advertisers reaching users in the EEA. Your consent solution therefore has to tell Google whether consent exists for advertising and analytics. Without that transmission, remarketing lists and part of the conversion measurement fall away. Technically more hangs on this than a formality: without a consent signal Google models the missing conversions, and bidding strategies carry on working with that estimate.

In addition, enhanced conversions ensure that conversions are attributed even when cookies are missing – via hashed contact data that arises anyway at purchase. That needs checking under data protection law and is not the right choice in every case.

How a dependable measurement basis is built across all channels is described on our page on web analytics.

Ads are labelled as such

Paid results appear in search results marked “Sponsored”. That is not a courtesy but a legal requirement in Germany: advertising must be distinguishable from editorial content. For you it means that a portion of searchers deliberately skips ads – and that organic placement therefore retains its own value.

What SEA can achieve – and what it cannot

Ads work from day one and stop working on the day they are switched off. That makes them suitable for periods where speed matters: product launches, seasonal business, the time while search engine optimisation is not yet carrying, or markets where there is nothing left to gain organically.

Their use as a measuring instrument is underrated: a few weeks of ads deliver more dependable data on which search terms actually bring enquiries than any research tool. Those terms are then the ones worth building a dedicated organic page for.

They do not solve problems that lie after the click. If the landing page does not convince, the offering is not competitive, or the form does not work on a phone, you are buying expensive traffic for nothing.

And they are not self-running. An account left unattended for three months will reliably spend money on search queries nobody planned for.

What we take on

• Building the account: structure, campaigns, ad groups, keywords
• Research of search terms and the competitive landscape
• Ad copy and ad extensions, tested continuously
• Setting up and verifying conversion tracking including the consent signal
• Choosing and steering the bidding strategy, budget allocation
• Maintaining negative keywords and cleaning up wasted spend
• Aligning ads and landing pages
• Regular reporting with recommended actions
• Taking over and tidying up existing accounts

If you would like an existing account reviewed or want to start fresh, describe your project via the contact page. For a first assessment, read access to your advertising account is enough.