FREE TOOL
CAC Payback Calculator for Ecommerce
How many orders does it take to earn back the cost of a new customer?
Use this free CAC payback calculator to compare up to 10 ad platforms. See how many orders cover CAC. You can also estimate your CAC payback period in months.
Contribution is what a sale leaves after its costs. Those costs include products, shipping, fulfilment and payment fees. This money can pay back CAC: the cost to win a new customer. Fixed bills, such as rent, come later.
Payback in orders
Example results
Whole orders needed to earn back the cost of one new customer, including their first order.
- Meta Ads CAC
- USD 90.0
- Contribution per order
- USD 39.0
Order value and costs
US Dollar (USD). USD is the fallback until country detection finishes. You can change it.
Choose a period to set dates, or choose Custom dates.
Other costs, if they apply
Find order value and costs in Shopify
Ask Sidekick for the figures it can find. Add costs recorded outside Shopify yourself.
Compare CAC recovery
Advertising platforms
Enter CAC, or calculate it from ad spend and new customers.
Platform 1
Find your Meta Ads CAC
Open your report, choose matching dates and look for Cost per Purchase for the Purchase event.
Use that figure as CAC only if the purchases are from unique new paying customers. Otherwise, enter ad spend and a new-customer count from your store or attribution report.
Open Meta Ads reportingYou may need to sign in and select your account. This link does not set dates or filter your report.
Payback in orders
Example results
Whole orders needed to earn back the cost of one new customer, including their first order.
- Meta Ads CAC
- USD 90.0
- Contribution per order
- USD 39.0
CAC recovery by platform
Contribution from 1 order, including the first order. The goal is to cover 100% of each platform’s CAC.
43.3% of CAC covered — USD 51.0 still to recover.
These colours show progress toward covering CAC. They are not industry benchmarks. Bars stop at 100%; the figures still show any amount above it.
Platform breakdown
Meta Ads
Repeat orders are needed to cover CAC.
- CAC per new customer
- USD 90.0
- Equivalent orders
- 2.3
- Whole orders, including first
- 3
- More orders after the first
- 2
- Money after CAC on first order
- -USD 51.0
Where each order’s money goes
- Average order value
- USD 100.0
- Products
- USD 50.0
- Shipping and fulfilment
- USD 8.0
- Payment fees
- USD 3.0
- Sales and affiliate commissions
- USD 0.0
- Other order costs
- USD 0.0
- Contribution before CAC
- USD 39.0
- Contribution margin
- 39%
What these results assume
Each order has the same average value and costs. The first order is included in the order count.
Contribution is the money left from a sale after its costs. Use it to cover CAC and regular bills.
The order count does not predict whether or when a customer will buy again.
Use the same dates and currency for ad spend and new customers. Keep the way you count new customers the same.
Two ad platforms may count the same customer. For blended CAC, count each new customer once.
Regular business bills, tax and interest are left out. Do not count the same ad cost or commission twice.
Changing the currency changes the unit shown. It does not convert your amounts.
HOW THIS TOOL WORKS
How CAC payback is calculated
Payback in orders
First, find the money left from each order after its costs. This is contribution.
Product costs are average items per order × product cost per item. Percentage fees use the order value. Fixed fees apply once per order.
Example: an order worth USD 100 has USD 50 of product costs, USD 8 of shipping and USD 3 of payment fees. It leaves USD 39. With CAC of USD 90, payback is 2.3 equivalent orders, so you need 3 whole orders, including the first.
If you enter contribution margin instead, contribution per order = order value × margin ÷ 100. The same costs must already be included in that margin.
Payback period in months
Example: CAC of USD 90 and monthly contribution of USD 15 per customer gives an estimated payback period of 6 months.
The average must include all customers in the new-customer group, including those who never buy again.
Example: USD 9,000 of contribution from 100 new customers over 6 months gives USD 15 per customer per month. This assumes a steady monthly pace. It is not the actual month when your customer group paid back its CAC.
CAC from ad spend
Example: USD 9,000 in ad spend brings 100 new customers. CAC is USD 90. Use matching dates, channels and customer counts. Do not count the same customer twice in a blended total.
CAC covered (%) = contribution per order or month × orders or months to compare ÷ CAC × 100
Example: one order leaves USD 39 and CAC is USD 90. That order covers 43.3% of CAC. Three similar orders leave USD 117 and cover 130%. The bar ends at 100%, while the figure shows the full amount.
What the result leaves out
Contribution is money left after the costs of a sale, before acquisition costs and fixed overhead. It is not final profit.
Regular bills, tax and interest are excluded. Do not count advertising or commissions twice. Currency selection changes the unit; it does not convert your amounts.
The orders tab assumes similar order values and costs. It cannot tell you whether a customer will return or when. The months tab is an estimate based on your monthly average.
Questions & Answers
What is CAC payback?
CAC payback tells you how much selling it takes to earn back the cost of winning a new customer. This calculator shows the number of orders needed or an estimated payback period in months.
Should I measure CAC payback in orders or months?
Use orders to see how many purchases must cover your acquisition cost. Use months when you have a monthly contribution average for a group of new customers. An order count alone cannot tell you how long payback takes.
What is contribution margin?
Contribution margin is the percentage of sales left after the costs that change with a sale, such as products, shipping, payment fees and commissions. That money helps cover CAC and regular business bills. Gross margin often leaves out shipping and payment fees, so it may be too high for this calculation. The Product Profit, Margin & Pricing Calculator can help you check those costs.
Can I use cost per purchase as CAC?
Only if those purchases are from unique new paying customers. Many ad reports also count repeat orders. If that is the case, use ad spend divided by new customers for the same dates. Platform help beside each row points to the relevant report.
Why might CAC not be recoverable?
If order costs use up all the sales money, there is no contribution left to cover a positive CAC. The same applies to a monthly contribution of zero or less. Check your costs and price before relying on more repeat orders.
Does this tell me whether my advertising is profitable?
It shows what is needed to cover CAC. It leaves out regular bills, tax and interest, and does not predict repeat purchases. Use the Acquisition Profitability Calculator to look more closely at your first-order advertising results.
How does CAC payback differ from customer lifetime value?
CAC payback asks when acquisition cost is covered. Customer lifetime value asks how much a customer is worth over a stated period. The Customer Lifetime Value Calculator helps you compare first and repeat purchases.
Does the calculator include ad spend, commissions and fixed costs?
Ad spend is included in CAC when you choose Ad spend / new customers. Applicable sales commissions can be entered as order costs. Fixed costs, such as rent and base salaries, are excluded. Do not enter the same cost in both CAC and order costs.
Do I need Shopify to use this calculator?
No. Enter figures from your store, accounts or advertising reports. The Shopify Sidekick prompts are optional help. The fixed payment fee can stay at zero if your provider does not charge one.
Can I save or share my results?
Use Copy for the full calculation, or Share with AI to copy a prompt and open ChatGPT, Claude or Grok. Your chosen email result does not sign you up for marketing. Saved figures may be restored in the same browser; copied results are the safest way to keep your own record.