CPA Calculator
Find advertising cost per recorded acquisition.
Formula and assumptions
Acquisition cost · CPA = Ad spend ÷ Acquisitions. Revenue per acquisition = Attributed revenue ÷ Acquisitions. ROAS = ratio(Attributed revenue,Ad spend).
Choose a consistent acquisition event. Revenue per acquisition is meaningful only when revenue is attributed to these acquisitions.
This tool processes inputs in your browser. Calculator values are not stored or sent by this plugin.
Further reading: Digital Marketing Services: Elevating Your Brand and Driving Sales in the Online Era
Related tools: Marketing ROI Calculator · ROAS Calculator
Page editor: Usman Arshad · Last edited: November 3, 2026
How to use this tool
Choose the relevant mode, enter Ad spend and complete the labelled fields. Use Calculate to review your result.
Worked example
Ad spend = 200, Acquisitions = 10, Attributed revenue (optional) = 500.
CPA = 20.00 currency units · Revenue per acquisition = 50.00 currency units · ROAS = 2.50×.
These example values are illustrative.
Interpreting the result
Compare the acquisition cost with the contribution earned on that conversion. Use the same event and attribution window for revenue and acquisition counts.
Assumptions and limitations
Choose a consistent acquisition event. Revenue per acquisition is meaningful only when revenue is attributed to these acquisitions.
Can I compare leads with purchases?
Use the same acquisition event across campaigns. A lead and a purchase represent different stages.