CAC Calculator
Sales + marketing spend in a slice ÷ newly acquired customers counted the same window.
Open calculator →CPA Calculator
Spend ÷ conversions for whichever conversion event you defined—lead, trial, purchase.
Overview
Use when comparing channels with stable conversion definitions. Changing the event between weeks invalidates trend reading.
When to use this calculator
- When spend and conversion count share the same definition
- When you line CPA up with LTV or payback targets
- When you compare lead CPA to purchase CPA honestly
- When multi-touch paths need a footnote but you still want a simple CPA
Rule of thumb
CPA is honest only when “conversion” means the same thing to finance and ads.
Terms used in this calculator
- CPA
- Ad spend divided by your chosen outcome—trial, signup, sale, demo, etc.
- Conversion rate
- Share of a clear baseline group—visits, sessions, leads—that finished the goal you named.
Calculator
Cost per acquisition
$60.00
Results are simplified estimates for educational purposes only and should not be treated as financial, accounting, legal, or tax advice. See our disclaimer for details.
Formula
Total spend ÷ conversions counted in the same attribution window as spend.
Example calculation
Using the default example values from the JSON seed for this tool:
- Ad spend
- 9000
- Conversions
- 150
Result: $60.00 (Cost per acquisition)
How to interpret this result
Spend per conversion event using your chosen conversion definition.
Align with LTV and payback targets for the same customer definition.
Multi-touch paths need attribution context beyond simple CPA.
Common mistakes
- Switching the conversion goal between lead and purchase without notice.
- Counting repeat purchasers as new acquisitions.
- Splitting multi-touch credit inconsistently across teams.
What to do next
Cross-check against LTV, payback months, or AOV depending on whether you optimized for revenue or logos.
How to improve this result
- Reduce form or checkout steps when CPA spikes without traffic change.
- Label events in ads the same way finance books revenue.
- Stop chasing low CPA leads that never close when your CRM says so.
Recommended tools
- Hotjar Heatmaps, recordings, and surveys to diagnose conversion friction.
- Meta Business Suite Manage Meta ad accounts, Pages, and reporting in one place.
FAQ
- Repeat purchasers counted?
- Usually no for acquisition CPA—decide per policy.
- Lead vs sales CPA?
- Don't merge them into one bucket on the report without relabeling.
- Why CPA rocketed overnight?
- Conversion tracking broke, inventory stockout, or delayed attribution—verify plumbing.
- Does this include partner commissions?
- Add them to spend numerator when partners close deals.
- Pair which calculators?
- LTV, ROAS (if revenue ties to ads), funnel conversion depending on objection.
Related calculators
CPC Calculator
Total ad spend ÷ measured clicks for the same scope and dates.
Open calculator →ROAS Calculator
Attributed revenue ÷ ad spend for the attribution window your team adopts.
Open calculator →Affiliate disclosure
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