Ad rank
Advertising mechanicsDefined term⦿ live instrument below
Ad rank is the score an ad auction assigns each participant to order the available slots. In the canonical search model it is the bid multiplied by a quality estimate, so a lower bid with higher predicted quality can legitimately outrank a higher bid.
Ad rank does double duty: it sets position, and it sets the payment of the advertiser one slot above, whose per-click cost is that next ad rank divided by their own quality plus one increment. Both effects are visible live in the auction simulator.
PosAdvertiserAd rank = bid × qualityPays
1B$2.50 × 8$2.41−4%
2C$3.20 × 6$2.68−16%
3A$4.00 × 4$2.26−44%
4D$1.80 × 5$0.51−72%
Advertiser B holds position 1 without the highest bid — quality is doing the work.
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