Google Ads
Impression Share
The percentage of eligible impressions you actually received.
Impression share reveals demand you are missing. Lost IS (budget) means you are capped by budget; lost IS (rank) means you are capped by ad rank.
The distinction matters: budget-limited campaigns need more money, rank-limited campaigns need better relevance or bids.
MyAd classifies every campaign's lost impression share and recommends the correct lever.