Updated December 2023
So, we’ve all seen ads appearing in Google Search, served via the Google Ads platform, but how does Google determine which order to show ads with the search engine results page (SERP)?
It’s not as straightforward as you might think!
Google uses a formula called Ad Rank, which ultimately decides which position ads will show in. So, let’s take a look at Ad Rank and the factors used to rank your ads.
What Is Ad Rank?
An auction determines the position of ads within the SERP. But, unlike with most auctions, the winner is not necessarily the highest bidder. In the Google Ad auction, the amount bid is only one factor used to determine the overall Ad Rank. The Ad Rank score is what determines ad positions in the search results.
So, if a pay-per-click (PPC) ad is the first listing at the top of the SERP, it won’t always have the highest bid behind it, but it will have the highest Ad Rank.
The highest ad positions typically deliver the highest number of clicks, which is why getting your ads to rank as high as possible matters.
Read on to learn about how Ad Rank is calculated and how to increase your Ad Rank in Google Ads.
How is Ad Rank calculated?
Although Google has never confirmed the exact Ad Rank formula, it has revealed the main ranking factors used within it.
Known Google Ad Rank factors include:
- The bid (the amount you’re willing to pay to have your ad displayed)
- Expected click-through rate (CTR)
- Ad relevance
- Landing page experience
- Expected impact of ad formats and extensions
These factors determine where your ad will sit on the page, and how much you will pay. We’ll talk about each of these in more detail later.
At this stage, we can hear some of you asking - but what about Quality Score?
What is Quality Score, and does it impact Ad Rank?
Okay, so this is where it gets a little tricky. You may have seen quality score discussed as one of the factors used in determining Ad Rank. The popular view of the Ad Rank equation looks something like the following:
However, Google says:
“Quality Score is an aggregated estimate of your overall performance in ad auctions, and is not used at auction to determine Ad Rank.” (Source:Google Ads Help)
So, why the confusion?
Quality Score in this context is specifically the 1-10 score shown in your Google Ads account, which is an aggregated estimate of your overall performance in ad auctions. Google states that, as it’s a historical grading of previous ad performance, it can’t be used at auction time to determine Ad Rank.
Although this Quality Score is not officially used to determine Ad Rank, Google does describe it as an estimate of your expected click-through rate, ad relevance and landing page experience. Google has also confirmed that higher quality ads can lead to lower prices and better ad positions, too.
So, even though Quality Score itself is a separate calculation, and is not officially within the Ad Rank formula, the same contributing factors also impact Ad Rank. So, although not strictly the same thing, raising one should raise the other. This is why ‘quality score’ is the popular term people use to refer to the group of quality factors Google uses in ad ranking.
With this in mind, the Google Ad Rank calculation looks a little more like this:
Now, let’s look at each of the contributing Ad Rank factors in a little more detail.
Google Ad Rank Factors in detail
The bid
Your bid is the maximum cost per click (CPC) you’re willing to pay. In the Ad Rank calculation, Google will likely give more weight to a higher CPC but, as we’ve seen, it isn’t the only factor.
As an advertiser, you’ll usually end up paying less than the maximum amount. If you have the highest Ad Rank, you’ll only pay enough to beat the CPC of the second ranked ad.
However, you still need to be prepared to pay this price - especially if bidding on this search term is exceptionally competitive. So, don’t inflate your bid to try and be seen if you or your business can’t afford the investment.
Expected click-through rate (CTR)
An ad’s click-through rate (CTR) is the proportion of users who click on the ad through to a landing page.
The expected CTR is an estimate of how likely it is users will click on an ad when shown.
Google calculates this likelihood by considering how well your chosen keyword has performed historically, taking into account the position of your ad.
Ad relevance
Ad relevance is about how much the keywords you are bidding on match the message in your ads.
You need to ask yourself: “If someone searches for this keyword and my ad shows up, will my ad be relevant?”.
If not, you need to rewrite your ad copy.
Your ad text must match with what the searcher is looking for. You want to make sure it’s appealing to encourage clicks. But don’t change your ad copy to be more relevant if your landing page doesn’t match.
Landing page experience
The user experience of ads is a significant consideration for Google.
That’s why Google Ads will consider how well your ad’s link provides users with what they were looking for. The usefulness of your landing page is calculated using a combination of automated analyses and human evaluation.
Google advises that you can improve your landing page experience in the following ways.
Offer relevant, useful and original content
Your landing page needs to follow on from your ad logically.
For example, if your ad is for a specific product, users should not land on your homepage.
But if your ad is for a general keyword, you don’t want to direct them somewhere too specific.
Promote transparency and foster trustworthiness on your site
Users need to know who you are and why they should trust you.
Make it easy for users to find your contact information and always be clear in explaining why you are asking customers for personal information.
Make mobile and computer navigation easy
Having an excellent overall user experience (UX) is crucial. So, ensure your landing page is accessible for customers – whatever device they’re using.
Pay attention to any unnecessary pop-ups which may annoy users.
Decrease your landing page loading time
Make sure your landing page loads quickly.
You can check your load times with Google’s PageSpeed Insights tool. This will also provide recommendations on how you can improve performance.
Make your whole site fast
Think beyond your landing page. Google considers the speed of your site overall.
To see how fast your site is on mobile, and to find out how to improve it, try Think With Google’s Test My Site feature.
Most of these steps are good practice for a website in general – not just when running an ad.
Expected impact of ad formats and extensions
Google Ads estimates how ad formats and extensions will impact your ad’s performance when calculating your Ad Rank.
There are various formats available within Google Ads, such as text, image, responsive (which automatically adjust to fit available ad spaces), app promotion, in-stream video, Product Shopping, Showcase Shopping, and call-only ads. These each serve different purposes and Google will consider how well they match with your ad. For more information on these, visit Google’s help guide on how to choose an ad format.
Extensions allow you to add elements such as a phone number or links to more specific pages on your site within your ad.
Other Factors impacting ad positioning
Beyond Ad Rank, there are another couple of factors that may influence whether or not your ad appears in search results.
Search context
Google looks at several factors to understand the intent of a user’s search and how relevant your ad is in this context.
These factors include:
- The user’s exact search term
- Their location
- The time of the search
- The device used (e.g. mobile or desktop)
Ad Rank also considers other ads and search results appearing on the same page, and other user signals and attributes. If Google feels your ad wouldn’t be relevant within the search context, it won’t be displayed.
Ad Rank threshold
The threshold is the lowest Ad Rank score needed for your ad to show.
If you don’t meet the threshold, your ad is ineligible to appear.
Google does not disclose information about the threshold, but the amount depends on a variety of factors, including:
- Ad quality: Lower quality ads need to meet higher thresholds, so Google maintains a high quality experience for users.
- Ad position: Ads that appear higher in the SERP will have a higher threshold than ads lower down the page.
- User signals and attributes: Such as location and device. Thresholds may vary country by country, or between desktop and mobile.
- The topic and nature of the search: The nature of the user’s search term. For example, targeting those looking to buy a car is likely to have a higher threshold than advertising local dance classes.
- Related auctions: Thresholds can also depend on auctions for related queries. For example, ads for the search term [wedding venue] could be informed by auctions for [venue hire] or [reception venue].
How to improve low Ad Rank
The main way to increase your Ad Rank in Google Ads is to take note of the factors discussed and implement a strategy to address these areas of your campaign.
To achieve a number one ranking ad, you need to think carefully about its relevance and the user experience. And don’t forget; ad ranking factors don’t stop with what your potential customers see in the SERPs. For an effective paid search campaign, you need to look after your landing page, too.
Understanding the fundamentals of paid search advertising is critical for running campaigns that perform well.
If you’re interested in learning more, check out our Google Ads (AdWords): Search training course.