What Google says
The report is available for Search, Shopping and Performance Max campaigns that meet a minimum threshold of activity. Google says it doesn't show insights when impression share is under 10%, and search partner traffic isn't included. For Search you can run it for keywords, ad groups or campaigns, and segment by time and device. Select the items, then choose Auction insights. (Google help center)
The statistics that matter most
Overlap rate is how often another advertiser's ad showed when yours did. Position above rate is how often their ad sat above yours when both showed. Outranking share is how often you ranked above them, or showed when they didn't. A competitor's impression share in your report is their share of the auctions they were eligible for, not of yours.
Use it on a brand campaign
Google doesn't restrict trademarks as keywords, so competitors can bid on your name. Run brand on exact match in its own Search campaign and Auction Insights shows exactly who appears on your brand searches, as we explain in Competitors are already bidding on your brand.
The Performance Max limit
For Performance Max, Google says the report covers only Search and Shopping ads on the Search Network, at account and campaign level, segmented by Search or Shopping. It blends every query the campaign entered, so it can't tell you who bids on your brand, and low competition there doesn't mean few rivals.
Common questions
What is Auction Insights in Google Ads?
Auction Insights is a report comparing your performance with other advertisers in the same auctions. For Search it shows impression share, overlap rate, position above rate, top of page rate, absolute top of page rate and outranking share.
What is overlap rate?
Overlap rate is how often another advertiser's ad received an impression when your ad also received one. A 60% overlap rate means their ad showed in 6 out of every 10 auctions where yours showed.
What is outranking share?
Outranking share is how often your ad ranked higher than another advertiser's ad, or showed when theirs didn't, across the auctions you entered together.
Why don't I see Auction Insights for some keywords?
Google only produces the report for keywords, ad groups and campaigns that meet a minimum threshold of activity for the selected time period. A longer date range can help on low-volume terms. Google also says the report doesn't show insights when impression share is under 10%.
Does Performance Max Auction Insights include YouTube and Display?
No. Google says Performance Max auction insights cover Search and Shopping ads served on the Search Network, segmented by Search or Shopping, at account and campaign level.