Impression share
Impression share is how much of the available ad showings you actually got. An impression is one showing of your ad. If Google thinks you were eligible for 10,000 showings and you received 6,000, impression share is 60%. Google splits the rest into budget (you ran out of money) and rank (your ad was not strong enough).
Theodor Lindfors, Founding Marketer ·
Formula
Impression share = impressions received / estimated eligible impressions
How impression share is calculated
Let's take a plumbing company as an example. The company buys Google ads to get homeowners who need a plumber this week. On Google Search, a homeowner typing plumber near me can see this company, a competitor, or neither. Impression share asks: of the searches Google thinks you were eligible for, how many did you actually show on.
Divide impressions received by estimated eligible impressions. Eligibility accounts for your targeting, approval status, bids, and quality signals. Let's take a plumbing company as an example. The company receives 6,000 impressions and was eligible for 10,000. Impression share is 60%. Google reports it for search, display, and shopping separately, and also as absolute top and top-of-page variants. Those are different heights on the results page, not the same number restated.
Lost impression share: budget vs rank
Lost to budget is a spending decision. The auction wanted to show the plumbing company and the campaign had nothing left, which usually points at pacing (whether spend is on track against the plan) or a budget set below what the account can profitably absorb. If 25 of every 100 eligible searches were missed because the daily cap hit at 2pm, that is a budget conversation.
Lost to rank is a competitiveness problem. Your bid, expected click-through rate, ad relevance, or landing page experience were not enough. Raising the budget will not touch it. See Ad Rank for what actually moves it. Let's take a plumbing company as an example. A 15% lost to rank is a quality and bid problem, not a "spend more" problem.
How to read impression share
High impression share is not automatically good. Owning 95% of a broad keyword like plumber usually means you are buying a lot of unqualified traffic. Owning 60% of emergency plumber tonight can be the better business. Let's take a plumbing company as an example. The company does not need every search. It needs the ones that become booked visits.
Impression share also differs from share of voice. Impression share is measured against your own eligibility inside one platform, not against competitors across a category. Let's take a plumbing company as an example. The company can have 80% search impression share and still be a small voice next to larger firms in Facebook ads and local radio.
Common impression share mistakes
- Treating 100% impression share as the goal on every plumbing-company campaign.
- Raising budgets to fix impression share that was lost to rank.
- Comparing impression share across campaigns with different keyword breadth.
Lemonado
How Lemonado helps with impression share
Lost impression share only becomes a decision when you know whether the missing budget was worth spending. A plumbing company can be missing searches that pay back, or missing junk queries that do not. Lemonado reads impression share next to spend and results, so raising a budget is a judgment rather than a reflex.