Free calculator
What does a new customer really cost you?
Put in what you spend on ads and how many new customers it brings in. Then see what the same customer costs when they find you on Google instead, and how long it takes to get there.
Your numbers
Paid ads
Google, Meta, the lot. Last month's total is fine.
Or your own time at an honest hourly rate. Add any apps you only pay for because of ads, like a product feed app.
Photos, video and design made for ads, averaged out per month.
First-time customers, not orders. Repeat buyers would have come back anyway.
SEO
An agency, a freelancer, or your own time at an honest hourly rate. Add any SEO tools or apps you pay for.
Extra first-time customers from organic search. If you're guessing, guess low.
SEO builds gradually. We assume new customers grow a little each month until they hit your number. This only affects the year-one cost.
Is each customer profitable? (optional)
Shopify shows this on the Analytics overview.
What's left of the sale after paying the supplier. Not markup.
The welcome code you give new customers. Set it to 0 if you don't run one.
Use 1 if you don't know. Most shops are somewhere between 1 and 2.
What a new customer costs you
Profit from one new customer
The difference that matters: switch off your ads and the customers stop that day. Stop paying for SEO and the pages you've built keep ranking for a good while.
Nothing you type is saved or sent anywhere. It all runs in your browser.
How to use it
Start with your ads. Put in last month's total ad spend and how many new customers it brought in. Not orders, new customers. Someone buying from you for the third time would probably have come back without the ad.
Then put in what SEO costs you a month, and a fair guess at how many extra new customers it could bring in once it's working. If you're not sure, guess low. The calculator also asks how long SEO takes to get going, because it does take time, and pretending otherwise is how people end up disappointed.
Open the optional section and add your average order value and margin, and you'll see whether each customer actually makes you money once you've paid to win them.
What is CAC?
CAC (customer acquisition cost) is what you spend on marketing divided by the new customers it brings in. Spend €5,000 on ads, win 100 new customers, and your CAC is €50.
It matters because every first order has to pay that back. If your profit on a typical first order is €30 and a customer cost you €50 to win, you're €20 down until they buy again.
Why SEO usually brings CAC down
Ads charge you for every click. Spend more and you mostly get more of the same, often at a higher price as you run out of the cheapest clicks.
SEO works the other way round. You pay to build pages that rank: collection pages, product pages, buying guides. Once they rank, the visits keep coming whether you're paying for each one or not. Your cost stays roughly the same while the customers grow, so the cost of each one falls.
The pages that do the heavy lifting are usually collection pages. For one Irish watersports client, the blog brought in 11,000 visits and 4 sales. Their collection pages brought in 95 sales. That's where we put the effort.
When ads are the better bet
To be fair to ads, there are times they make more sense:
- A brand new shop or product line that nobody is searching for yet
- Stock you need to clear this month, not next year
- Products with very small search demand, where there's not enough traffic to win
Most of the shops we work with run both. SEO brings the average cost down over time, and ads fill the gaps.
Finding your numbers in Shopify
New customers: Analytics > Reports, and look for the first-time vs returning customer reports. Your ad platforms will also tell you how many purchases they claim, but they tend to be generous with themselves.
Average order value is on the Analytics overview. For margin, take what you sell a product for, subtract what you paid the supplier, and divide by the selling price.
What to do with the result
If SEO comes out cheaper, the next question is where to start: which pages, which searches, and how long before it pays. If ads come out cheaper at your numbers, that's worth knowing too, before you pay anyone for SEO.
See what this looked like for a surf shop we worked with, or see how we do Shopify SEO.
