Impression Share (IS)
% of eligible impressions your ads actually received
% of eligible impressions your ads actually received
Why It Is Critical
Impression Share tells you what percentage of the searches you were eligible to show for you actually showed up in. A 45% impression share means that for every 100 searches that could have triggered your ad, your ad only appeared 45 times. This is critical data for budget and bid decisions - it tells you whether you are losing visibility because of budget constraints or because your Ad Rank is too low.
How It Works & Underlying Dynamics
The Two Types That Matter Most: • Search Lost IS (Budget): You had the Ad Rank to show but your daily budget ran out. Fix: increase budget or tighten targeting to spend more efficiently. • Search Lost IS (Rank): Your Ad Rank was too low to win the auction. Fix: improve Quality Score, increase bid, or add more extensions.
'Before increasing a budget, always check how much IS is being lost to Rank vs Budget. Increasing budget to compensate for a low Quality Score is throwing money at the wrong problem.'