How Do Google Ads Work? The Auction, Costs and Campaign Types Explained (2026)

Google Ads is Google’s advertising platform. Businesses pay to show ads on Google search results, YouTube, Gmail, Google Maps and millions of partner websites and apps.

Most Google Ads campaigns run on a pay per click model. You choose the searches you want to appear for, set a budget, and pay when someone clicks your ad. The platform was called Google AdWords until 2018, so “how does AdWords work” and “how does Google Ads work” ask the same question.

Ads sit apart from organic results. They are labelled “Sponsored”, and paying for ads does not change where your website ranks organically.

The Google Ads auction runs every time someone searches on Google or visits a site that shows ads. It decides in a fraction of a second which ads appear and in what order.

Here is what happens behind every search:

1. Someone searches. For example, “employment solicitor London”.
2. Google finds matching ads. It looks for advertisers whose keywords match the search.
3. Ineligible ads drop out. Ads that are disapproved, targeted elsewhere or below Google’s minimum quality thresholds are removed.
4. Google calculates Ad Rank. Each remaining ad gets a score for this search.
5. Ads are ranked. The highest Ad Rank takes the top position. Google runs a separate auction for each ad location on the page.
6. You pay when clicked. If someone clicks your ad, you are charged. If not, you pay nothing.

Your own keywords do not compete against each other. If two keywords in your account match the same search, Google picks one (Google Ads Help).

What decides Ad Rank?

Google uses six factors to calculate Ad Rank (Google Ads Help):

Factor	What it means
Your bid	The most you are willing to pay for a click
Ad and landing page quality	How relevant and useful your ad and page are to the searcher
Ad Rank thresholds	The minimum score needed to show at all, and higher scores for top positions
Auction competitiveness	How close your Ad Rank is to the ads around you
Search context	The search terms, location, device, time of day and other results on the page
Ad assets and formats	The expected impact of extras like sitelinks and phone numbers

Ad Rank is recalculated for every auction. Your position for the same keyword can change from one search to the next.

Why doesn’t the highest bid always win?

The highest bid does not always win because quality and assets count alongside the bid. Google says a lower bidder with stronger assets can still win a higher position.

In practice, a relevant ad leading to a relevant page can beat a competitor bidding more. This is why two firms bidding on the same keyword often pay very different prices.

You pay the minimum needed to keep your position, not your full bid. Google describes the actual cost per click as “only what’s minimally required to clear the Ad Rank thresholds” and beats the ad ranked below you (Google Ads Help).

Your maximum bid is a ceiling. Google says you are never charged more than it, unless you use automated bidding or bid adjustments.

Click prices vary hugely by sector. Across the legal campaigns we manage, average CPCs run from £14.64 for property disputes to £98.67 for work accident claims. At a 20% landing page conversion rate, that is £73 to £493 per lead.

The same budget buys very different volumes:

Practice area	Monthly budget	Average CPC	Clicks	Leads at 20% conv.	Cost per lead
Property disputes	£2,000	£14.64	136	27	£73
Work accidents	£2,000	£98.67	20	4	£493

Source: MagnifyLab campaign data.

A high CPC is not a bad sign on its own. A £98.67 click is profitable if the matter is worth £20,000. Judge Google Ads on cost per client, not cost per click.

How do Google Ads budgets work?

You set an average daily budget for each campaign. On a busy day, Google may spend up to twice that amount, but over a month it will not charge more than 30.4 times your daily budget (Google Ads Help).

A £50 daily budget can spend up to £100 on one day. Across the month, the maximum charge is £1,520.

Quality Score is a 1 to 10 rating Google gives each keyword to show how your ad quality compares with other advertisers. It is a diagnostic, not a direct input into the auction (Google Ads Help).

It is based on three components, each rated above average, average or below average:

• Expected clickthrough rate. How likely people are to click your ad for that keyword.
• Ad relevance. How closely your ad matches the intent behind the search.
• Landing page experience. How relevant and useful your page is once someone clicks.

The score itself does not set your price. The ad quality it measures does feed into Ad Rank, so improving the three components usually lowers what you pay per click.

Google matches searches to your keywords using match types. The match type decides how close a search has to be to your keyword before your ad can show (Google, 2026).

• Exact match. Shows for searches with the same meaning as your keyword. “Divorce lawyer” can match “solicitor for divorce”. The most control.
• Phrase match. Shows for searches that include the meaning of your keyword, with words around it. “Divorce solicitor” can match “local divorce solicitor”.
• Broad match. Shows for searches related to your keyword. It reaches everything phrase and exact match reach, and more.

We start new accounts on exact and phrase match. We introduce broad match only once an account has at least 20 conversions a month and strong negative keyword lists.

Negative keywords stop your ad showing for searches you do not want, such as “jobs”, “free” or “course”. The search terms report shows the real searches that triggered your ads, so you can add new negatives every week.

AI Max for Search goes further. It uses your landing pages and ads to match searches beyond your keyword list, and can rewrite ad text. Google began upgrading campaign level broad match to AI Max from September 2026 (Google, 2026).

Google Ads offers six main campaign types. Each shows ads in different places and suits a different goal.

Campaign type	Where ads show	Best for
Search	Text ads on Google search results	Capturing people actively looking for a service
Performance Max	All Google channels from one campaign	Scaling once conversion data is strong
Demand Gen	YouTube, Gmail, Discover and the Display Network	Reaching and remarketing to new audiences
Video	YouTube	Brand awareness and video led campaigns
Shopping	Product listings in search and the Shopping tab	Retailers selling products online
App	Search, Google Play, YouTube and partner apps	Driving app installs

Source: Google Ads Help. Display campaigns are moving into Demand Gen, starting in 2026 (Google Ads Help).

For most service businesses, Search is the core campaign. It reaches people at the moment they need help, and it gives the clearest link between spend and enquiries.

Bidding tells Google how much you are willing to pay in each auction. You can set bids yourself, or let Google set them automatically.

• Manual CPC. You set a maximum cost per click for each keyword. Full control, but slow to manage at scale.
• Maximise clicks. Google sets bids to get as many clicks as possible within your budget.
• Maximise conversions. Google sets bids to get as many enquiries or sales as possible within your budget.
• Target CPA. Google aims for an average cost per acquisition you choose.
• Target ROAS. Google aims for a return on ad spend you choose, using the value of each conversion.

The automated options, known as Smart Bidding, set a new bid for every auction using signals such as device, location and time of day. They only work as well as your conversion tracking. If Google is counting the wrong actions, it will bid for the wrong people.

Smart Bidding also needs history. A new account with no conversion data often starts on maximise clicks or manual CPC, then moves to automated bidding once enquiries are flowing.

Google Ads appear at the top and bottom of search results, on Google Maps, YouTube, Gmail, Discover and across millions of partner websites and apps.

AI search is the newest placement. Google is rolling out ads in AI Mode to more countries and plans to bring them to the UK in the final quarter of 2026 (Google, 2026). The same auction principles apply: relevance and quality decide who shows.