Digital marketing term
Impression Share
Impression Share is a metric that shows, as a percentage, how many impressions an ad actually received out of the total impressions it was eligible for.
Detailed explanation
This ratio shows how much of all the search or impression opportunities an advertiser was eligible for were actually captured. Every percentage point below 100% represents impressions missed due to a budget limit, a low bid, or a weak quality score.
This metric is typically split into budget-lost and rank-lost shares; this split shows which area needs optimization.
Marketers use this data to decide whether they need to increase budget or improve ad quality, and to make strategic adjustments during periods of heavy competition.
Frequently asked questions
- Why might impression share be low?
- Insufficient budget or a low Ad Rank can cause some eligible impression opportunities to be missed.
- How is impression share increased?
- Increasing budget or raising quality score to improve Ad Rank both increase impression share.
Related terms
Internal links for the topic cluster — read these concepts together.
- Ad RankAd Rank is the ranking score that determines the position an ad appears in on platforms like Google Ads for a given search, combining bid amount, ad quality, and expected impact.
- Quality ScoreQuality Score is Google Ads' 1–10 rating of a keyword's expected relevance, based on expected CTR, ad relevance, and landing page experience.
- SEMMarketing for visibility in search results — the umbrella can include SEO, but most teams mean paid search. Budget, bids, and Quality Score run independently from organic ranking work.
- ReachReach is a core visibility metric that counts the number of unique users who saw a piece of content or an ad at least once within a given period.
- TargetingLimiting who sees an ad by demographics, interests, behavior, or a custom audience list. Tight targeting cuts waste; over-narrowing kills learning and scale.
- Share of VoiceA brand’s share of category visibility in ads or conversation. It is not the same as share of spend; it is share of being seen.