CPA Calculator

Calculate Cost Per Acquisition (CPA) from ad spend and conversions. See if your CPA is profitable relative to your average order value.

Part of our Business Calculators collection.

CPA Calculator

Free online calculator

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To calculate implied ROAS

How to Use This Calculator

  1. 1

    Enter total ad spend and conversions.

  2. 2

    Optionally enter target CPA and AOV.

  3. 3

    See CPA vs target and implied ROAS.

CPA Formula

CPA = Total Ad Spend / Total Conversions
Implied ROAS = AOV / CPA
Profit per Conversion = AOV − COGS − CPA

Target CPA = AOV × Gross Margin %
(i.e. spend no more than your margin on acquisition)

Example Calculation

Example: $2,000 spend, 40 conversions

Inputs

adSpend: 2000conversions: 40targetCPA: 60avgOrderValue: 120

Result

CPA: $50 ✅ Under $60 target | ROAS: 2.4×

$2,000 / 40 = $50 CPA. $120 / $50 = 2.4× ROAS.

Frequently Asked Questions

What is a good CPA?
Depends entirely on your margins and AOV. Your max CPA = AOV × gross margin %. A $100 product with 50% margin = max $50 CPA to break even. Target CPA should be below this.
How do I lower CPA?
Improve ad creative and targeting (higher CTR), improve landing page conversion rate, better audience segmentation, and test different offers. A 50% improvement in conversion rate halves your CPA.

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