What is impression share?
Impression share is a fairly self-explanatory metric, it simply refers to what share of the possible impressions for your chosen keywords your ad campaign is getting on the search network of the most popular search engines. Similarly, there’s “absolute top impression share” which measures what percentage of your advertisements are being shown in the top position on searches for your targeted search terms. There can only be one of these for each search so this number will always be lower than the overall search impression share. Impression share is an important competitive metric for understanding your ad rank.
There are quite a lot of different types of impression share variations. On paid search, for example, you are able to track your bing or google ads impression share at the search campaign level, ad group level, and even at the keyword level. You’ll also be able to compare metrics with the search lost impression share, which will give you the share of impression that you lost instead of gained. Those 2 metrics show account for a total of 100% impression. Alternatively, if you have display or shopping campaigns, your ads are probably running on the display network, for this scenario you might want to look at the display impression share, as it gives you an idea of the percentage of impressions that your display ads were able to get.