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Marketing

CPA Calculator

Calculate Cost Per Acquisition — the average cost to acquire one paying customer from your ad campaigns.

$

Your CPA

CPA

$20.00

Each conversion costs $20.00 on average.

$3,000 ÷ 150 conversions

Ad Spend

$3,000

Conversions

150

Formula

CPA = Ad Spend ÷ Conversions
Ad SpendTotal advertising spend in the period
ConversionsNumber of completed desired actions (purchases, sign-ups, etc.)

Example Calculation

You spend $3,000 on Facebook Ads and generate 150 purchases.

CPA = $3,000 ÷ 150 = $20.00

Each conversion cost you $20 on average. Compare this to your product profit to assess campaign viability.

How to Interpret CPA

CPA should always be evaluated against the revenue or value generated per conversion. If your average order value (AOV) is $50 and your CPA is $20, you have a 2.5x ROAS — that may or may not be profitable depending on your margin.

Target CPA = (AOV × Gross Margin) ÷ Target ROAS. Anything above this threshold means you are spending more to acquire customers than they generate in profit.

Common Mistakes

  • Not accounting for repeat purchases — a high CPA can be acceptable if LTV is strong.
  • Mixing conversion types (e.g., purchases + newsletter sign-ups) in a single CPA calculation.
  • Comparing CPA across channels without adjusting for attribution windows.
  • Ignoring product margin — a $20 CPA on a $25 product with 30% margin is unsustainable.

Frequently Asked Questions

It depends on your product price, margin, and LTV. A CPA below your gross profit per order is generally a baseline minimum. Many businesses target a CPA that is 20–30% of AOV for a profitable direct-response campaign.

Disclaimer: Results produced by this calculator are estimates for informational purposes only and do not constitute financial, business, or professional advice. Actual results will vary based on your specific business conditions, market factors, and other variables. Always consult qualified professionals before making business decisions.