Divide spend by acquired customers to get CPA, the metric bids and budgets are optimised against.
Dividing spend by the number of customers gives the unit economics of the channel. The reciprocal — customers delivered per unit of currency — is shown alongside, because that is the figure to maximise when a budget is fixed. Unit cost is the only number that lets you compare channels with wildly different budgets, and it is the input every bid and budget decision ultimately rests on.
Cost Per Acquisition
Cost Per Acquisition = Campaign spend ÷ Customers acquired
Cost Per Acquisition = Campaign spend ÷ Customers acquired Dividing spend by the number of customers gives the unit economics of the channel. The reciprocal — customers delivered per unit of currency — is shown alongside, because that is the figure to maximise when a budget is fixed.
Unit cost is the only number that lets you compare channels with wildly different budgets, and it is the input every bid and budget decision ultimately rests on.
This calculator takes 2 inputs: Campaign spend, Customers acquired. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.