Google Ads Auction - Search Ads (Real Time Bids)

Factors for Ad rank 

• Max CPC  BID- max amt. willing to pay per click
• Quality Score  

  1. CTR   -    ( clicks / impressions ) % 

  2. Ad relevance

  3. Query relevance

  4. Landing page relevance

G*Ads Rank Formula

Ad Rank = (MAX CPC Bid) x (Quality Score)

Actual CPC per bidder (Uses 2nd Price Auction) = 

( Ad Rank of Advertiser in position below bidder ) /  (Bidder’s Quality Score)

https://www.optimizesmart.com/complete-guide-to-google-adwords-analytics/