CPA Calculator (Cost Per Acquisition)
Calculate CPA, break-even CPA, ROAS, and true profit per order including ad spend. Works for Facebook Ads, Google Ads, TikTok Ads, and any paid channel.
By Marginory team · Online sellers with hands-on experience across Etsy, Shopify & PODUpdated Fee data verified against official platform documentation
Campaign Metrics
$
%
$
Per-order Costs
$
$
Campaign Results
Conversions / orders20.0
Cost per click (CPC)$0.50
Cost per acquisition (CPA)$25.00
ROAS1.20x
Total revenue$600.00
Profitability
Break-even CPA$17.00
Profit per order (incl. CPA)-$8.00
Total campaign profit-$160.00
Profit margin (incl. ad cost)-26.7%
How this is calculated
Conversions: Clicks × Conversion rate
CPA: Ad spend / Conversions
CPC: Ad spend / Clicks
ROAS: Revenue / Ad spend
Break-even CPA: Average order value − Product cost − Other costs
Profit per order: AOV − Product cost − Other costs − CPA
Assumptions:
- Conversion rate: % of clicks that result in an order
- Other costs includes platform fees + shipping per order
- Break-even CPA: CPA at which profit = 0 (no other costs considered beyond product + other costs)
Frequently Asked Questions
What is CPA and how do I calculate it?
CPA (Cost Per Acquisition) = Ad spend / Conversions, where Conversions = Clicks × Conversion rate. Spend $200 with 1,000 clicks at a 4% conversion rate: conversions = 40, CPA = $200 / 40 = $5. That's what you pay in ad spend for each customer acquired, separate from product cost or fees.
How do I find my maximum affordable CPA (break-even CPA)?
Break-even CPA = Average order value − Product cost − Other costs (fees + shipping). A $40 AOV with $12 product cost and $6 in fees/shipping leaves $22 — that's the most you can spend acquiring a customer and still break even. Set actual campaign CPA targets 20–30% below this number to leave room for profit.
How is CPA different from ROAS and CPC?
CPC (cost per click) measures traffic cost only. CPA measures the cost of an actual sale — CPC divided by conversion rate. ROAS (Revenue / Ad spend) measures the inverse relationship: how much revenue each ad dollar returns. A campaign can show a great ROAS while still having a CPA above your break-even line if AOV is high but margin is thin — always check both metrics together, not just one.
What's a common mistake sellers make with CPA targets?
Using one CPA target across every product. A $15 item and a $150 item can have very different break-even CPAs even at the same margin percentage, because fixed per-order costs (like a $0.30 payment fee) are a much smaller share of the higher-priced order. Calculate break-even CPA per product or price tier, not storewide.
How do I lower my CPA without cutting ad spend?
Three levers move CPA without touching your budget: improving conversion rate (more buyers from the same clicks), improving AOV (higher revenue per acquired customer, which raises your break-even CPA), and tighter audience targeting (higher-intent clicks convert more often). Raising conversion rate from 2% to 3% alone cuts effective CPA by roughly a third.
Does this calculator work for any ad platform?
Yes — CPA math is platform-agnostic. Whether you're running Facebook/Meta Ads, Google Ads, TikTok Ads, or Pinterest Ads, enter your own clicks, conversion rate, and ad spend and the formulas apply the same way. Typical CPA benchmarks vary by channel (Google Shopping often runs $10–30, Facebook $15–40, TikTok $8–25 for impulse-buy products), so compare your result to your specific channel's norms.