How to use this calculator
- Enter campaign spend, attributed acquisitions.
- Choose a display currency, then select Calculate. Results also update after a brief pause while you edit.
- Read the result with the assumptions below. Export details or save a second scenario to compare your choices.
Formula and method
Assumptions and limitations
Use figures for the same entity, currency and reporting period. The denominator must be positive. This ratio is descriptive and has no universal pass/fail threshold.
Worked example
With campaign spend = 600, attributed acquisitions = 30, cpa is approximately 20.
What the result means
Specify what counts as an acquisition and include the same campaign costs and attribution window.
Common questions
How should I interpret cpa?
Specify what counts as an acquisition and include the same campaign costs and attribution window.
What should I check before using this result?
Use figures for the same entity, currency and reporting period. The denominator must be positive. This ratio is descriptive and has no universal pass/fail threshold.
Methodology and transparency
Calculation specification reviewed on 2026-10-14. Mathematical implementation is tested against independent reference fixtures. This does not imply review by a licensed financial professional. Read the testing and precision policy.