How does the Google Ads auction work? The mechanism explained without jargon

Have you ever wondered why some businesses always appear in first position on Google, even when they are not the biggest in their sector? The answer is not the highest budget. It lies in a precise mechanism Google calls Ad Rank, and understanding it means understanding why some advertisers get two to three times more clicks than their competitors for the same budget.

A myth to bust: no, the highest bidder does not always win

This is the most widespread misconception about Google Ads. As we explained in our first article, Google Ads is not just an advertising platform, it is a complete system where every element counts. And the auction system is at its heart.

Many business owners think the platform works like a simple auction: whoever pays the most appears first. The reality is far more nuanced, and far more favourable to advertisers who work smart.

Take a concrete example. A plumber in Lyon bids €8 per click. His competitor bids €4 per click. Who appears first? Not necessarily the first one. If the €4 competitor has more relevant ads, a better landing page and a solid performance history, he will win first position while paying less. It is pure maths.

In 2026, 78% of Google Ads spend is managed by automated bidding strategies. But even with automation, the underlying mechanism stays the same: it is always the combination of bid + quality that decides who appears and at what price.

The Google Ads auction: the formula that decides everything

Every time someone searches on Google, the Google Ads auction runs in a fraction of a second: invisible to the user, decisive for you. For each eligible advertiser, Google calculates a score called Ad Rank. That score determines whether your ad appears, in which position, and how much you actually pay per click.

Ad Rank = Bid × Quality Score × Impact of assets

Calculated in real time for every auction · The exact formula is proprietary, but Google has confirmed these 3 pillars.

What makes this system particularly interesting for advertisers who optimise properly: a high Quality Score acts as a permanent multiplier. It doesn't just lower your cost per click; it improves your position, increases your visibility and strengthens the effectiveness of all your future bids.

Quality Score: the lever 80% of advertisers neglect

Quality Score is a rating from 1 to 10 that Google assigns to each of your keywords. It assesses the overall quality of the experience you offer the searcher by combining three distinct components:

COMPONENT 1:

Expected CTR

Google estimates the likelihood that your ad will be clicked when it is shown. It is the heaviest criterion in the score.

~60% of the score

COMPONENT 2:

Ad relevance

How closely does your ad match the searcher's intent? The keyword should appear naturally in your ad.

~20% of the score

COMPONENT 3:

Landing page experience

Is your landing page relevant, fast and useful for the searcher? Google analyses the content and the UX.

~20% of the score

In practice: what Quality Score changes for your budget

The numbers speak for themselves. In 2026, accounts with a Quality Score of 8 to 10 pay on average 37% less per click than the market median. Conversely, accounts with a score below 4 pay 64% more than the same median.

−37%

Average CPC for accounts with a Quality Score of 8–10 vs the market median

+64%

Average CPC for accounts with a Quality Score below 4

2–3×

More clicks generated on the same budget with a high vs low QS

Here is a concrete worked example to make it tangible:

With a €3 bid and a Quality Score of 10, you beat a competitor bidding €8 with a mediocre score. That is the power of the system, and it is precisely why optimising Quality Score is one of the highest-return actions you can take on your account.

Ad assets: the often-forgotten third pillar

The third Ad Rank factor is the expected impact of your ad assets. Assets are additional information you can add to your ads: sitelinks, phone number, customer reviews, location, prices, promotions…

These assets have a double effect: they visually enrich your ad and mechanically improve your Ad Rank. An advertiser using relevant assets will consistently rank higher than a competitor with the same bid and Quality Score but no assets.

Good news: 

Ad assets are free. You only pay if someone clicks on your ad, not on the assets themselves. It is one of the few Google Ads levers that improves your performance without adding a single cent to your budget.

In 2026, automation changes the rules, but not the fundamentals

With Smart Bidding and Performance Max, Google increasingly manages bids automatically. In 2026, advertisers using automated bidding strategies report on average a 22% lower cost per conversion compared with manual CPC. But beware: automation does not remove the importance of Quality Score, it amplifies it.

Here is why: when you hand your bidding over to Google's AI, the algorithm constantly optimises based on your quality signals. An account with a strong Quality Score gives the AI better material to work with. A poorly structured account with weak ads feeds the AI bad signals, and it then optimises towards poor results.

The automation trap:

Many advertisers think switching on Smart Bidding is enough to optimise their campaigns. It isn't. Google's AI is only as good as the data it receives. Without a worked-on Quality Score, accurate tracking and a clean account structure, automation amplifies existing problems rather than solving them.

3 concrete actions to improve your Ad Rank right now

1) Structure your ad groups by precise intent. 

One ad group = one keyword theme = highly relevant ads. The stronger the consistency between keyword, ad and page, the higher your expected CTR.

2) Optimise your landing pages. 

The landing page must match the search intent exactly. Fast loading, relevant content, a clear CTA: Google analyses all of this to rate the experience you offer.

3) Enable every relevant asset. 

Sitelinks, callouts, call assets, reviews, promotions… Every relevant asset improves your Ad Rank and increases the visual size of your ad in the results.

TAKE THE NEXT STEP

Your Quality Score may be holding back your campaigns without you knowing

A low Quality Score means a permanent extra cost on every click you buy, and a lower position than your budget deserves.

Most of the accounts we audit have significant room for improvement on this lever alone.

At VD Adsconsulting, we analyse your Quality Score, the structure of your ad groups, the relevance of your landing pages and your use of assets in detail. You leave with a concrete, prioritised optimisation plan, with no commitment.