Google is making cost-per-acquisition (CPA) based bidding available to AdWords advertisers through a new Conversion Optimizer tool. Advertisers specify a maximum CPA bid, and then the tool will use historical information about the campaign to automatically generate an optimal CPC bid for each auction.
Advertisers still pay per click, but no longer have to manually adjust their bids to reach CPA goals.
Conversion Optimizer requires that a campaign currently uses AdWords Conversion Tracking and has at least 300 conversions in the last 30 days. Ads can appear on both the search and content network.
Google also offers CPA-based pricing on its pay-per-action (PPA) beta, where advertisers pay only when an action they define occurs, such as a purchase on their site or newsletter sign-up.
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