Free tool
Break-even CPL calculator
A good cost per lead is not a benchmark from someone else's account. It is the number your own economics can pay. Enter what a customer is worth, your margin and how many leads become customers: the calculator returns the highest CPL you can afford and the CPL that keeps the profit you want.
Your numbers
Results
| Gross profit per customer | — |
| Revenue per lead | — |
| Break-even cost per customer (CAC) | — |
| Break-even CPL | — |
| Target CPL | — |
| Break-even ROAS | — |
| Current cost per customer | — |
How to use the break-even CPL calculator
Three numbers decide the most you can pay for a lead: what a customer brings in, how much of that is profit, and how many leads turn into customers. The calculator multiplies them. Everything runs in your browser, so nothing you type leaves the page.
- Revenue per customer. Use the first sale if you need the money back quickly. Use lifetime value only if you are sure of it and can finance the wait until it comes in.
- Gross margin. The share of that revenue left after the cost of delivering the product or service: hours, materials, fees. Not net profit: overheads are paid from what is left after acquisition.
- Lead-to-customer rate. Customers divided by leads, measured over a window at least as long as your sales cycle. If deals close in 30 days, a week of data understates it.
- Share of gross profit to keep. Break-even means every euro of gross profit goes back into ads. The target CPL keeps the share you choose.
The formula
Break-even CPL = revenue per customer × gross margin × lead-to-customer rate. It is the same as break-even CAC × lead-to-customer rate, because a customer costs your CPL divided by the rate at which leads close.
Target CPL = break-even CPL × (1 − share of gross profit to keep).
Example: a service sells at €2,000 per customer with a 60% gross margin, and 8% of leads become customers. Gross profit per customer is €1,200, so you can spend up to €1,200 to win one customer. With 8% of leads closing, that is 12.5 leads per customer, which puts the break-even CPL at €1,200 ÷ 12.5 = €96. If you want to keep 40% of the gross profit, the target CPL is €96 × 0.6 = €57.60.
| Input | Example | Result |
|---|---|---|
| Revenue per customer | €2,000 | Gross profit €1,200 |
| Gross margin | 60% | Break-even CAC €1,200 |
| Lead-to-customer rate | 8% | Break-even CPL €96 |
| Share of profit to keep | 40% | Target CPL €57.60 |
How to read the result
The break-even CPL is a ceiling, not a goal. Above it, each customer from that traffic costs more than the gross profit it brings. Between the target and break-even you are still profitable, just less than you planned. Below the target you have room: either scale the budget, or accept a higher CPL for leads that close better.
The break-even ROAS shown next to it is the same limit seen from the revenue side: revenue divided by ad spend must reach 1 ÷ gross margin before acquisition pays for itself.
The close rate is not one number
This is where most CPL targets go wrong. The calculator takes one lead-to-customer rate, but your traffic does not have one. Leads from one creative may close at 12% and leads from another at 3%; the same is true of two landing pages. Each source therefore has its own break-even CPL, and a "cheap" source can be the expensive one once you divide by how few of its leads buy.
That is why the useful comparison is per ad and per landing page, not per campaign. Run the calculator once per source, or use the CPL vs CPQL calculator to compare two sources on cost per qualified lead. The cost per qualified lead guide explains how to get the qualification data from your CRM.
DropCPL measures the real CPL of every ad and landing page from your own leads, so you can hold each source against its own limit. Start free →
Common mistakes
- Using revenue instead of gross profit. A CPL set on revenue spends money you never had.
- Using lifetime value you cannot finance. If the value arrives over 18 months and the ads are paid this month, cash runs out before the maths works.
- Measuring the close rate on a short window. Recent leads have not had time to close, so the rate looks lower and the limit tighter than it is.
- Trusting the platform's lead count. If Meta reports more leads than reached your CRM, the real CPL is higher than the one in Ads Manager. See real CPL vs platform CPL.
Related reading: what is a good cost per lead on Facebook ads, how to reduce cost per lead on Meta ads, and the definitions of CPL, CPA and ROAS.
FAQ
What is a break-even CPL?+
It is the highest cost per lead at which acquiring a customer still pays for itself: revenue per customer × gross margin × lead-to-customer rate. At that CPL, the gross profit of each new customer is entirely spent on the ads that brought it in.
How do I calculate the maximum cost per lead I can afford?+
Multiply the gross profit of one customer by the share of leads that become customers. A customer worth €1,200 in gross profit with a 10% close rate allows at most €120 per lead. To keep part of that profit, multiply by the share you are willing to spend.
Should I use lifetime value or the first sale?+
Use the first sale if you need to recover ad spend quickly or cannot finance the wait. Lifetime value raises the limit, but only if the repeat revenue is reliable and you can carry the cost until it arrives.
What is the difference between break-even CPL and target CPL?+
Break-even CPL leaves you with zero gross profit from acquisition. Target CPL keeps the share of gross profit you decide to protect, so it is always lower. Steer by the target and treat break-even as the line you do not cross.
What if I do not know my lead-to-customer rate?+
Count customers and leads from the same period in your CRM, using a window at least as long as your sales cycle. Until you have that, run the calculator with a pessimistic and an optimistic rate to see the range your CPL has to stay within.