How do you calculate break-even CPA?

Start with the sell price the customer pays. Remove output VAT, because in the EU and UK the sticker price includes it. Remove payment processing, typically around 2.9 percent plus a fixed amount. Remove the landed cost — goods, freight per unit, duty and any unrecoverable import VAT. What is left is the break-even CPA. Most calculators skip the VAT step and overstate the figure by a fifth.

Is a 3x markup enough for dropshipping?

It depends entirely on your landed cost, and the rule of thumb hides that. On a product landing at EUR 5.80, a 3x markup gives a EUR 17.40 sell price and a break-even CPA of EUR 8.83. At 4x it is EUR 13.46, at 5x it is EUR 18.08. Whether EUR 8.83 is workable depends on your niche's actual acquisition cost, which the multiple cannot tell you — the multiple is a heuristic for the number, not the number.

Why does a higher price improve margin faster than it improves CPA headroom?

Because margin is a ratio and CPA headroom is an amount. Going from EUR 14.95 to EUR 39.95 on the same product moves margin from 46 to 67 percent — impressive but bounded. The break-even CPA moves from EUR 6.88 to EUR 26.81, nearly quadrupling. The percentage flatters and the amount is what you actually spend, which is why the amount is the better number to plan with.

The number to compute before you test anything

Q: What is break-even CPA?

The most you can pay to acquire one customer before that sale stops making money. It is the sell price minus output VAT, payment fees and landed cost — what remains is what you can hand to an ad platform. If your actual cost per acquisition is below it you are profitable on that unit; above it you are buying revenue at a loss.

Margin tells you whether a product works in principle. Break-even CPA tells you whether you can afford to advertise it — and that is the decision you are actually making when you look at a supplier listing. Here it is, worked from a real cost model.

2 September 2026 · figures from the model inside MurmMargin

Break-even CPA is what remains of the sale after everything that is not advertising. Sell price, minus output VAT, minus payment fees, minus landed cost. Spend less than that per customer and the unit makes money. Spend more and you are buying revenue at a loss, however good the margin percentage looks.

The same product at five prices

One product landing at €5.80 a unit — €4.20 goods, freight split across 50, duty and import VAT in the EU. Only the sell price changes:

Sell price	Markup	Margin	Break-even CPA
€14.95	×2.6	46%	€6.88
€19.95	×3.4	54%	€10.87
€24.95	×4.3	60%	€14.85
€29.95	×5.2	63%	€18.84
€39.95	×6.9	67%	€26.81

Look at what the two columns on the right do. Margin climbs from 46% to 67% — a respectable but bounded improvement, and one that gets less impressive the further you go. Break-even CPA goes from €6.88 to €26.81, almost four times.

That gap is the whole argument for planning in amounts rather than percentages. Margin is a ratio and it flatters; CPA headroom is money and it is what you actually hand to Meta. Two products can share a 60% margin and be completely different businesses to run, because one leaves you €4 a customer and the other leaves you €40.

What the 3× rule actually buys you

Every guide teaches a 3–5× markup on landed cost. It is a decent heuristic and it hides the number it is a heuristic for. Same product, same €5.80 landed:

Markup	Sell price	Break-even CPA
3×	€17.40	€8.83
4×	€23.20	€13.46
5×	€29.00	€18.08

Whether €8.83 per customer is workable is not a question the multiple can answer. In a niche where acquisition runs €6, 3× is comfortable. Where it runs €12, 3× loses money on every sale while displaying a healthy-looking 3× markup and a 49% margin. The rule of thumb is not wrong; it is just answering a different question than the one you have.

The step most calculators skip

In the EU and UK the price a shopper sees includes VAT. That money was never yours. A calculator that takes the sell price, subtracts cost and calls the remainder profit has overstated it by roughly a fifth before it starts.

The full sequence, in order:

Sell price — what the customer pays.
Minus output VAT — 21% of the gross in the Netherlands, 20% in the UK.
Minus payment fees — around 2.9% plus a fixed amount, charged on the gross.
Minus landed cost — goods, freight per unit, duty, and import VAT that you cannot reclaim.
What remains is break-even CPA.

Landed cost has its own ordering trap: duty is charged on goods plus freight, and import VAT on the duty-inclusive total. Getting that sequence wrong understates cost — the one direction an error must never go, because it tells you a bad product is fine. And below the customs threshold there is no duty at all, which changes the answer more than most people expect.

What this number cannot tell you

Your actual CPA. That comes from your ad account, not from arithmetic. Break-even CPA is the ceiling you are aiming under.
Whether the product sells. A generous break-even on something nobody wants is still a generous break-even on nothing.
Net profit. Returns, chargebacks, refunds and your own time are not in this figure. It stops at contribution per unit, deliberately.
Repeat purchases. If customers buy twice, you can pay more than break-even to acquire them once — but that is a bet on retention you do not yet have evidence for.

MurmMargin computes this on the supplier listing you are looking at. Type your sell price and it prints the break-even CPA as the headline, with every assumption — VAT registration, payment fees, freight split, duty band — written beside it.

How MurmMargin works →→

Questions

What is break-even CPA?

The most you can pay to acquire a customer before the sale stops making money.

How do I calculate it?

Sell price, minus output VAT, minus payment fees, minus landed cost. What remains is it.

Is a 3× markup enough?

On a €5.80 landed cost it leaves €8.83 per customer. Whether that is enough depends on your niche, which the multiple cannot tell you.

Why not just use margin percentage?

Because you spend money, not percentages. Two products at 60% margin can leave you €4 and €40 respectively.

See also: MurmMargin · The de minimis cliff · MurmAds · Writing