What is Impression Share?

Glossary Term

Impression Share.

Learn what Impression Share means in modern search and SEO.

Part of speechnounOriginLatin impressio (pressing into) + Old French partager (to share)

A Google Ads metric showing the percentage of eligible impressions your ads actually received versus the total available impressions.

Impression Share (IS) is the ratio of impressions an ad receives to the total number of impressions it was eligible to receive. If a campaign's Impression Share is 60%, the ads appeared in 60 out of every 100 auctions they qualified for and missed 40%.

Lost Impression Share Diagnoses

Google Ads breaks down lost IS into two categories: IS Lost (Budget)—auctions missed because the daily budget ran out—and IS Lost (Rank)—auctions missed because Ad Rank (Quality Score × bid) was too low. Each category requires a different remedy: increasing budget vs improving Quality Score or bid.

Impression Share in SEO Context

In SEO, 'impression share' is not a native metric, but Google Search Console's Performance report shows Impressions (how many times a site appeared in SERPs), which functions analogously. Share of Voice tools like Semrush and Ahrefs estimate organic impression share by combining average ranking position with estimated search volume across a keyword set.

Related Terms

Quality Score

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