eCPC stands for “enhanced cost per click.” As a Google smart bidding strategy, it utilizes Google’s algorithm to adjust your bid to drive the maximum number of conversions. It can be used on both the Google Search and Display Network.
What is ECPC Bidding?
Here’s how it works. Imagine your max CPC bid is $0.50. If a conversion is likely (but bids are trending a little pricier than your max bid) Google will raise your bid, maybe to $0.75, in order to show your ad. On the flip side, if your ad is going to show at your current max bid and Google thinks your ad is less likely to lead to a conversion, then Google will lower your bid. In this example, your bid might be lowered to $0.25.
Similarly, if CPCs are out of your budget for a particular auction, Google could lower your bid (sometimes even as low as $0) to avoid the auction all together. Google does this in order to direct your spend only to ad auctions that are 1) likely to result in a sale and are 2) winnable in your current bid range.
In the past, eCPC bidding could only adjust your bid 30% higher or lower than your max CPC bid, but following an update in 2017 eCPC bidding can exceed that limit and is essentially uncapped. Google reassures users by saying that eCPC attempts to stay close to your max CPC.