Impression Share
Impression share is the percentage of times your ad appeared out of all times it was eligible to appear. It shows how much of the available auction you are winning.
Impression share tells you what fraction of available ad auctions you are actually entering and winning.
What Impression Share Means in Marketing
Every time someone searches a keyword you bid on, an auction runs. You either enter that auction and potentially show your ad, or you do not. Impression share is the ratio of auctions where your ad appeared to the total number of auctions where it was eligible to appear.
Impression Share = Impressions earned ÷ Total eligible impressions × 100
An impression share of 40% means you appeared in 40 out of every 100 auctions you could have entered. The other 60% went to competitors, or to your own limitations, either a budget that ran out or a quality score too low to win.
This metric matters because it tells you whether you are leaving demand uncaptured. If you are running ads on “digital marketing agency Kerala” and your impression share is 30%, there are seven searches happening for every three you are showing up for.
How Impression Share Works
Impression share is broken into components that identify what is costing you:
- Lost to budget: Your daily budget ran out. You were eligible but could not enter the auction because the money was spent.
- Lost to rank: Your ad rank was too low. Rank is determined by your bid multiplied by your Quality Score. Low scores on landing page experience, ad relevance or expected click-through rate all reduce rank.
The fix differs by cause. Budget loss is solved by increasing spend or improving efficiency so the budget stretches further. Rank loss requires improving the ads and landing pages, not just raising bids.
Impression Share Example
A performance marketing account runs ads for a seasonal sale. On the first day, impression share is 65%. By day three, it drops to 40%, and the “budget lost” column climbs. The daily budget is exhausted by early afternoon, and the campaign goes dark for the highest-intent evening search period. Raising the daily budget or shifting budget from underperforming ad groups would recover those missed auctions.
Why Impression Share Matters for Marketers
Impression share is the link between your account settings and the real competitive situation. It answers the question your other metrics cannot: are you even showing up?
A low conversion rate looks different depending on impression share. If you are converting 2% of the traffic you see but only capturing 20% of available impressions, the real opportunity is much larger than your current results suggest. Fixing impression share first makes every subsequent conversion rate optimisation more meaningful.
Frequently Asked Questions
What causes low impression share?
Two things: budget and quality. Budget-limited impression share means your daily cap runs out before the day does, so you stop entering auctions. Rank-limited impression share means your quality score or bid is too low to win auctions you are entering. Google Ads breaks these out separately in the Impression Share columns, which tells you which problem to fix.
Should you always try to maximise impression share?
No. A high impression share on unprofitable terms means you are winning auctions you should lose. The goal is high impression share on the terms that convert and make money, not on everything in your account. Chasing 100% impression share on broad match keywords is a fast way to exhaust budget on irrelevant queries.
What is search lost impression share by rank versus by budget?
Search Lost IS (Rank) is the share of eligible auctions you lost because your ad rank was too low, which means your Quality Score or bid needs work. Search Lost IS (Budget) is the share you lost because your daily budget ran out. Budget loss is easier to fix. Rank loss often requires improving landing pages, ad relevance or both.