Before You Spend Another Euro on Ads, Check These Numbers
A little while ago I sat down with a store owner who wanted to start running ads. He was excited. He had the product, the website, the budget — he just needed someone to "turn the ads on."
So I asked him one question first: how much does your product sell for?
Twenty euros.
I had to be honest with him. I told him: running profitable ads on this is going to be really hard. Not impossible — but hard. And it had nothing to do with his ads, his audience, or his creative.
It was the math.
He looked confused, so I walked him through it. Here's the same walkthrough — in plain language — so you can check your own store in about five minutes.
The thing most people get wrong
Facebook and Instagram ads work like an auction. You're not really paying for "ads" — you're paying to get in front of people, and you're bidding against every other store chasing the same customers. That price goes up every year, and it goes way up around the holidays.
So the real question isn't "How do I make my ads cheaper?"
It's "Does my product make enough money per sale to pay for a customer acquisition — and still leave me a profit?"
That's exactly where my €20 friend got stuck. After his product cost, shipping, packaging and fees, there just wasn't enough left in each sale to pay for a customer and still keep something. Better ads can't fix that. The stores that win at Meta aren't the ones with the fanciest creative — they're the ones whose numbers leave room to pay for customers.
"Ultimately, the business that can spend the most to acquire a customer wins" Dan Kennedy
The 3 things that decide what a customer costs you
Every euro you spend runs through three simple numbers.
1. How much it costs to be seen (CPM) This is the price to show your ad to 1,000 people. It's set by how many other stores are fighting for the same audience. You don't fully control it — but you do control whether you can afford it.
2. How many people click (CTR) Out of everyone who sees your ad, how many actually click it? This is your creative doing its job. Better ad, more clicks, cheaper traffic.
3. How many buy (conversion rate) Out of everyone who lands on your site, how many actually check out? This is your website's job — fast pages, a clear offer, reviews, an easy checkout.
Here's how the three connect. Say you spend €1,000 with a CPM of €20:
Get seen: €1,000 ÷ €20 = 50 batches of 1,000 → 50,000 people see your ad
Get clicks (CTR 2%): 50,000 × 2% = 1,000 visitors to your site
Get sales (conversion 2%): 1,000 × 2% = 20 customers
Cost per customer: €1,000 ÷ 20 = €50 to get one buyer
Now you can see it clearly: the same €1,000 could get you 10 customers or 100, depending on those two middle numbers. A better ad doubles your clicks. A better website doubles your buyers. Move both and your cost per customer drops fast.
Put those together and you get the number that really matters: what it costs you to get one customer.
More competition pushes that cost up. Better ads and a better website push it down. That's the whole game.
But there's one more number — and it's the one that decides whether you actually keep any money.
The number that makes or breaks you: your profit per sale
Getting a customer is one thing. The question is whether that customer is even worth getting.
Your profit per sale is what's left after the real cost of an order:
What the customer pays − (product cost + shipping + packaging + payment fees + any discount)
That leftover is all you have to pay for ads. This is exactly why the €20 product was so tough: once you take out costs, there might be €8–€10 left — and if a customer costs €30 to get, you lose money on every order, no matter how good the ads look.
Quick gut check: thin profit per sale means almost no room to pay for ads. Healthy profit per sale means you can keep buying customers even when ad prices climb. That cushion is the whole difference between a store that scales and a store that stalls.
Three products, same ads, same €1,000 budget — very different endings
Here's the part that surprises most people. Let's hold the ads completely still — same CPM, same click rate, same conversion rate — and change only the price of what you sell.
In all three cases the ads behave identically: a €20 CPM, 2 out of every 100 people click, and 2 out of every 100 of those buy. Your €1,000 budget gets the same 1,000 clicks and the same 20 customers every time — and every customer costs you the same €50 to get.
The only thing that changes is your product's price and the profit it carries. Watch what that does.
Product 1 — the €25 item (bleeding money)
Sells for €25, costs €10 to make and ship → €15 profit per sale
20 customers, each costing €50 to get
The result:
Money in: 20 × €25 = €500
Profit before ads: 20 × €15 = €300
After paying for ads: €300 − €1,000 = −€700
You pay €50 to win a customer who only leaves €15 behind. You lose €35 on every single sale. The ads aren't broken — the price is simply too low to ever cover the cost of a customer. This is exactly where my €20 friend was stuck.
Product 2 — the €60 item (almost there)
Sells for €60, costs €25 → €35 profit per sale
Same 20 customers, same €50 each
The result:
Money in: 20 × €60 = €1,200
Profit before ads: 20 × €35 = €700
After paying for ads: €700 − €1,000 = −€300
Same ads, same customers — but now each sale leaves €35 instead of €15. You're still €15 short per customer, but watch how fast the gap is closing. A higher price did that, not better advertising.
Product 3 — the €120 item (making money)
Sells for €120, costs €45 → €75 profit per sale
Same 20 customers, same €50 each
The result:
Money in: 20 × €120 = €2,400
Profit before ads: 20 × €75 = €1,500
After paying for ads: €1,500 − €1,000 = +€500
Nothing about the advertising changed. Same CPM, same clicks, same conversion, same €50 to get a customer. But a €75 profit per sale easily swallows that €50 — so you keep €25 on every customer and walk away €500 ahead.
Same ads. Same budget. Same €50 customer. Three completely different endings — decided entirely by what you sell and the margin it carries. This is why selling a higher-priced, higher-margin product (or bundling your way up to one) is so often the fastest path to ads that actually make money.
Try it yourself: the profit calculator
Reading the math is one thing. Feeling it is another.
Below is a simple calculator. Plug in your own numbers — what your product sells for, what it costs you, your budget, how many people click, how many buy — and watch it tell you, instantly, whether you'd make or lose money each month.
Play with it. Drop your click rate and watch your cost per customer jump. Bump your order value and watch a losing store turn profitable. Try the same numbers my €20 friend had. In two minutes of sliding numbers around, you'll understand this better than any blog post can explain — and you'll know exactly which lever to pull in your own store.
Go ahead — break it, push it, find your own break-even point. Then come back and read the last part, because there's a simple game plan for fixing whatever you just found.
Drop in your numbers and see, instantly, what a customer really costs you and whether you keep a profit.
Your numbers
CPM is what it costs to show your ad to 1,000 people. It jumps during the holidays (Nov–Dec) and in crowded niches, because everyone is bidding at once.
What a typical customer spends in one order.
Product, shipping, packaging and payment fees — everything to fulfil one order.
Typical coupon or promo. Leave 0 if none.
Of people who see your ad, how many click it?
Of people who visit your site, how many buy?
Your result
What to do next
So what did I tell the €20 guy to do?
Two things. First, make each order bigger. When the order value goes up, suddenly there's enough room to pay for a customer and still profit. The easiest ways to do that:
Increase price — since he didn't have a customer base, he could have increased prices of the product.
Bundles — sell 3 together as a set for a little less than 3 singles. Bigger order, happier customer.
Buy more, save more — "buy 2, get 10% off." Pushes people to grab an extra unit.
Upsells — at checkout, offer a bigger size or a matching add-on ("add the travel size for €8").
Downsells — if they say no to the upsell, offer a cheaper option so you still bump the order ("not ready for the bundle? add one more for €5").
Subscriptions — for anything people reorder (like supplements), a "subscribe & save" turns one sale into many.
Free shipping threshold — "free shipping over €50" nudges people to add one more item.
Second, improve the numbers you can actually control. You can't do much about CPM (that's the auction, and it's mostly out of your hands). But the other two are yours to win:
CTR (more clicks) — better creatives is the fastest lever. Stronger hook in the first 3 seconds, real UGC and customer videos instead of polished stock, clear offer in the ad itself, and testing several angles instead of betting on one.
Conversion rate (more buyers) — fix the website: faster pages, a clear offer above the fold, reviews and trust badges, simple checkout, and obvious shipping/returns info. Going from 1 in 100 buyers to 2 in 100 literally cuts your cost per customer in half.
Repeat purchases — a simple post-purchase email flow or a subscription option turns one-time buyers into the repeat sales that made Store 3 win.
Lower product cost — negotiate with your supplier or order bigger batches. Every euro saved drops straight into profit.
Meta ads aren't magic and they aren't a gamble. They're a multiplier. Profitable numbers? Ads pour fuel on the fire. Broken numbers? Ads just burn cash faster. Get the math right first — then scale with confidence.
Not sure where your store stands? If you want a second set of eyes on your numbers, we're happy to help — and we'll walk through it together.
