Contents
- Impression share relates the impressions obtained to the total impressions the campaign was eligible for.
- The two loss columns, budget and rank, tell you which of the two levers unlocks volume.
- It is not available on Performance Max, which leaves those campaigns with no coverage diagnosis at all.
Definition
Impression share measures the proportion of possible impressions your ads actually obtained on the Search Network.
Formula
Impression share = impressions obtained divided by estimated eligible impressions. The remainder splits into two losses: the one due to budget, and the one due to ad rank.
Worked example
A campaign shows 42% impression share, 31% lost to budget and 27% lost to rank. It is capturing less than half the accessible market, and the main room to manoeuvre is budgetary: raising the budget should mechanically bring volume, whereas working on ad quality would only address the second third.
Orders of magnitude
On a brand campaign, an impression share below 80% usually signals a problem: nobody should be outranking you on your own name. On competitive generic queries, shares of 20% to 50% are frequent and perfectly healthy: chasing 100% would cost far more than the marginal volume returns.
The most common mistakes
- Trying to maximise impression share. The last points of share come at a premium, on the most contested and often least profitable auctions.
- Reading share without the losses. It is the split between budget loss and rank loss that tells you what to fix.
- Looking for it on Performance Max. It is not exposed there, and no reliable equivalent exists for those campaigns.
Where to find the metric
In Google Ads only, the Search impression share, Search lost IS (budget) and Search lost IS (rank) columns, at campaign and ad group level. Equivalent columns exist for Display and for absolute top of page.
Frequently asked questions
The Adwise team connects Google Ads, Meta Ads, LinkedIn Ads, GA4 and Search Console so agencies and freelancers can run their campaigns from a single place.