CPL vs CPQL vs CAC vs ROAS: four formulas, one funnel, a worked example

CPL, CPQL, CAC and ROAS are usually explained one at a time. In practice they are four points on one funnel: money is spent, a lead arrives, the lead proves qualified, a sale is made. Here is a worked example with all four formulas on one week of one project: a driving school advertising on Meta (Facebook and Instagram), 2–8 October 2026.

The week’s inputs: $885 of spend, 863 leads, 335 qualified leads, 36 sales and $5,297 of revenue recorded in the CRM. All four metrics come from these five numbers.

Product screen · capip.uz

What is CPL, and how is cost per lead calculated?

CPL measures what it costs the ads to get one person to leave a request. It is a number about the advertising itself: does the creative catch attention, is the form easy to fill in, is the audience expensive. Ads Manager shows it by itself, so a media buyer’s report usually opens with it.

CPL does not show who the lead is: a real buyer and someone who filled in the form out of boredom cost the same.

What is CPQL, and how is cost per qualified lead calculated?

Of the 863 leads, 335 turned out qualified: 39%. So CPQL is 2.6 times the cost per lead: not $1.03 but $2.64. It tells whether the ads bring the right people.

CPQL is known long before the sale: once a manager has spoken to the lead and moved its stage. That makes it the fairest number for a new creative’s first week. If the definition of a qualified lead changes, CPQL changes too: agree on it once and leave it alone.

How is CAC calculated?

The week had 36 sales against 335 qualified leads: 11%. One customer cost $24.58, the price of 24 leads. CAC is the business owner’s number: it is set against the profit one customer brings. If the profit is above CAC, the advertising pays; if below, it loses money, however cheap the lead.

Here CAC holds ad spend only. A full CAC adds the media buyer’s or agency’s fee, the sales team’s pay and the tools. Ad-spend CAC is enough to compare creatives and campaigns; the economics of the business need the full one.

What is ROAS, and how is it calculated?

A ROAS of 5.99× means that every $1 of advertising has $5.99 of revenue recorded against it in the CRM. ROAS is not profit: cost of goods, rent and salaries are not in it. At a 50% margin, a ROAS of 2× only just covers the ad spend.

The second weak spot is revenue itself: in the report it is the amounts written into CRM deals. When a manager leaves the amount empty, the sale is counted, nothing is added to revenue, and ROAS comes out lower than it really is. At this driving school managers enter about half of the amounts, so 5.99× is ROAS on recorded revenue.

CPL vs CPQL vs CAC vs ROAS: what is the difference?

Each row down is a step closer to the money and is known a step later: CPL the same day, CPQL after the manager’s call, CAC and ROAS after the payment.

Why is cost per lead misleading on its own?

Because CPL is an average and sees only the first step of the funnel. Two creatives of the same driving school, same week:

A media buyer who looks only at cost per lead adds budget to the first creative and switches off the second: the ad that sells. In the same week 23 creatives spent $386 without a single sale, 44% of the budget.

Quality can differ even at the same lead price. At a learning centre (2–8 October 2026) two creatives had almost the same cost per lead, $2.79 and $2.97: none of the first one’s 14 leads was qualified, 18 of the second one’s 24 were. In the same project a qualified lead cost $2.20 in one creative and $71.40 in another, a 32-fold gap. More in which ad creative sells.

Where does each number come from: the ad account or the CRM?

The four formulas hold five numbers. One comes from the ad account, the rest from the CRM.

So CPL can be worked out from the ad account alone. For CPQL, CAC and ROAS you have to know which ad each CRM lead came from. With lead forms and website requests the sale is closed in the CRM, outside the advertising, and Meta does not see it by itself: that week, on its own, it saw 863 leads and none of the 36 sales.

There are two ways to join the two sides. One is a report: the CAPI Platform report puts Meta’s spend and the CRM’s outcome (Bitrix24, amoCRM or capiCRM) on one row for every creative. The other is sending the outcome back to Meta: a CRM stage goes through the Conversions API as a custom event named QualifiedLead or as a Purchase event.

Meta reports that advertisers who used the Conversions API for CRM and optimised instant forms for the number of qualified leads saw a 19% lower cost per quality lead on average (a budget-controlled A/B test, 567 advertisers, 13–27 January 2025). That is Meta’s test, not a result of CAPI Platform.

What do you do with these four numbers each week?

1. 1

   Compare CPL with last week

   If leads suddenly got dearer, look for the cause in the creative, the audience or the form. Never switch a creative off on CPL alone: it warns, it does not pass sentence.

2. 2

   Sort creatives by CPQL

   Stop those that spend money and bring no qualified leads. If the qualified share is low, ask the advertising: who is it bringing?

3. 3

   Set CAC against the profit per customer

   Many qualified leads and few sales is a question for the sales team. If CAC is below the profit, add budget to the creatives that sell.

4. 4

   Check the amounts before ROAS

   How many sales have no amount? Fill those in first, then split the budget between campaigns by ROAS.