If there is one thing Google Ads is good at, it is producing lots of numbers to look at. From impressions to individual device performance, there is no end of data to consider. But the key is always to turn those numbers into “what’s next” moments that guide you toward your next campaign optimizations.
One helpful metric in this is the search impression share. What is it? I’m glad you asked.
The search impression share is usually expressed as a percentage, which reveals how often your ads were shown, compared to how often they were eligible to show.
One of the great benefits of Google Ads is that you get a lot of control over how often your ads show. You can daypart your ads to show only during business hours, for example, or have your ads only show on weekends.
Often the most important factor that influences how often your ads are displayed is the budget size. Most clients don’t have the budget to show their ads 100% of the time. So the ads show for searches some of the time, but not all of the time.
The amount of the time they do show is your search impression share. For example, if you have a 30% search impression share, that means your ads show roughly 30% of the time. (We have sometimes called it Share of Voice.)
To see what your search impression share is, just add that column to your dashboard view in Google Ads.
I supposed it could be debated if search impression share is really important. Most clients care about more business tangible things like conversions, and ad clicks. Things that really demonstrate an action as a result of the campaign.
Search Impression Share is Important Because it Provides Context Around What Other Numbers Mean.
But search impression share is similar in nature to the click-thru rate–it provides context for your other data. Where click-thru rate is the intersection of ad impressions and ad clicks, search impression share puts context around the larger search universe your ads compete in.
Search impression share will tell you the general ad coverage you are experiencing in your campaigns.
There are a few ways to increase your search impression share.
Increase your campaign budget. This is the easiest one, but sometimes often the most unlikely. If you handle campaigns for clients, they frequently their budgets set for the year. This makes the simple act of adding more budget not so simple. If you handle paid search internally for your company, you may face similar budgeting cycles. We all wish we could just apply more money to the campaign whenever we want. If you have spare change laying around, adding it to the campaign will influence your search impression share.
How much will your search impression share change along with the budget? The general rule of thumb is also simple math. If you are spending $X and you are getting 30% search impression share, then doubling your budget will get you 60%.
Dayparting. Limiting your ads to times when they may be more effective is always a sound strategy. For example, if you run a restaurant, you could daypart Thursday morning to Sunday afternoon, when data suggests people are making weekend plans.
But be aware this only changes search impression share during the time your ads are running. Obviously if your ads are off, you are getting a 0% share.
Also, shutting your ads off from midnight to 6AM may have no effect on your search impression share, if you get little traffic during that time anyway. You have to make strategic choices on when your ads will show versus other high traffic times when they may not.
Negative keywords. Having a nice, tightly controlled negative keyword list can sometimes be the difference between a good, working campaign, and a terrible one. Using negative keywords to control how your ads match to keywords can influence your search impression share by ensuring your ads show only for the terms that really matter.
Keyword match types. This is the traveling buddy to negative keywords. The two should often be looked at in tandem. Along with negative keywords, this is the biggest factor in how your ads show and match to active searches. Next to the budget allocation, this is probably the next biggest factor in how your search impression share shakes out.
Search impression share helps give you context to the larger search universe. It helps you see where your ads fit into the landscape of the daily searcher online. That reveals some nuance to your other numbers when deciding if a campaign is working or not, and importantly, what to do next.