Campaign math
CPA Calculator
Calculate cost per acquisition, required ad spend, or conversions. Choose the metric you need, then enter the other two campaign numbers.
What do you want to calculate?
The highlighted metric is the result.
Total media spend for the period
Purchases, leads, installs, or other actions
Average ad cost for each conversion
Calculated CPA Required ad spend Expected conversions
Conversions per 1,000 ad spend
Budget for 100 conversions
Enter values greater than zero
Both input metrics are required before the result can be calculated.
Currency changes the display symbol only. Enter every monetary value in the same currency.
The formulas
How to calculate CPA, spend, and conversions
CPA connects campaign cost to results. Once you know any two values in the relationship, you can calculate the third without changing the conversion definition or reporting period.
Cost per acquisition
CPA = Ad spend ÷ Conversions
Required budget
Ad spend = CPA × Conversions
Expected results
Conversions = Ad spend ÷ CPA
Example
A campaign spends 2,500 and generates 100 purchases. Dividing 2,500 by 100 gives a CPA of 25. At the same efficiency, 200 purchases would require 5,000 in ad spend.
From benchmark to campaign
Research the ads behind the acquisition cost
Use Eachspy to compare long-running creatives, landing pages, advertisers, and spend signals before committing budget to a new angle.
CPA calculator questions
CPA means cost per acquisition or cost per action. It measures the average advertising cost required to generate one purchase, lead, registration, or other conversion you define.
Divide total ad spend by the number of conversions. For example, 2,500 in ad spend divided by 100 purchases produces a CPA of 25.
Yes. Choose the metric you want to calculate, then enter the other two. The calculator can solve for CPA, total ad spend, or the number of conversions.
Use the event your campaign is optimized around, such as a completed purchase, qualified lead, app install, or registration. Keep the conversion definition consistent when comparing campaigns.
A good CPA is lower than the value or contribution margin generated by the conversion. There is no universal benchmark because margins, repeat purchases, and conversion quality vary by business.
CPA usually measures campaign spend divided by a chosen action. Customer acquisition cost can include a broader set of sales and marketing costs required to acquire a new customer.
Start with the contribution margin available before advertising. Your target CPA should stay below that break-even ceiling and leave room for the profit you want to earn per conversion.
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