CPC (Cost Per Click)

CPC (Cost Per Click) is the realised price paid for an individual ad click in an Amazon auction. It is what shows up in the Spend column of your reports divided by the Clicks column — the average CPC for a row of data:

Avg CPC = Spend / Clicks

CPC and bid are not the same thing. The bid is the maximum you offered; the CPC is what the second-price auction actually charged you (one cent above the second-highest bid, then shaded by Amazon's relevance score). In a healthy account, CPC is consistently 40–80% of bid.

Why CPC matters as a separate metric

Tracking CPC alongside bid surfaces three diagnostics no other metric reveals:

1. Bid headroom. If average CPC is 35% of bid, the auction is uncompetitive and you can probably reduce the bid 15–20% without losing clicks. If average CPC is 95% of bid, you're constantly hitting the ceiling and either need a higher bid or are bidding on a keyword where everyone else is bidding to the limit.
2. Auction-pressure changes over time. Rising CPC at constant bid means new advertisers have entered the auction (common around Q4, Prime Day, and new product launches in your category).
3. Placement cost variance. Top of Search CPC is structurally higher than Rest of Search CPC because the placement modifier stacks on top of the bid before the auction. CPC per placement is the input to ACOS-per-placement analysis.

CPC vs. ACOS

CPC is one of three terms in the ACOS equation:

ACOS = (Clicks × Avg CPC) / Ad Sales = Avg CPC / (CVR × ASP)

Three levers control ACOS: CPC (down), CVR (up), ASP (up). When ACOS rises, diagnose which lever moved. A rising CPC at flat CVR is an auction-pressure problem (raise the bid or accept lower volume). A flat CPC at falling CVR is a listing or stock problem (fix the PDP). A flat CPC at falling ASP is a pricing problem.

CPC by placement

Amazon's placement report shows CPC for each of Top of Search, Product Pages, and Rest of Search. The pattern is consistent across categories:

The placement modifier you set determines how heavily you tilt the spend mix toward each. See Placement Bid Modifier.

Common mistakes

• Confusing bid and CPC. Saying "my bid is €0.80" when you mean "my CPC is €0.80" leads directly to over-bidding. The bid that produces a €0.80 CPC is usually €1.20–€1.60.
• Optimising for low CPC. Cheap clicks that don't convert are more expensive than expensive clicks that do. CPC matters only relative to CVR.
• Ignoring rising CPC at flat CVR. Treat as a leading indicator that auction pressure is intensifying — typically 2–4 weeks before competitors' new product launches show up in your SERP.
• Reporting CPC at campaign rollup level. Campaign-average CPC hides the placement and keyword variance that matters. Decompose by placement and keyword for any bid decision.