CPL (Cost per Lead) is the average marketing cost you pay to acquire one lead—typically a signup, trial request, form submission, or demo booking. In web analytics terms, a “lead” is a predefined Goal and often a Micro-Conversion on the path to a Macro-Conversion such as a purchase or contract. CPL sits alongside pricing models like CPC, CPM, and CPA and is a staple KPI in lead-generation funnels.
Teams track CPL per Campaign, channel, or Source using UTM tagging (UTM). You can measure it in GA4 or in alternative stacks like Matomo, Plausible, or Simple Analytics when you combine ad spend with lead events.
How is CPL calculated?
Formula:
CPL = Total Campaign Cost ÷ Number of Leads
Example: Spend €1,200 and generate 80 leads → CPL = €1,200 ÷ 80 = €15.
To keep CPL meaningful:
- Define the lead event clearly (Conversion vs. Conversion Rate).
- Separate “raw leads” from qualified leads (MQL/SQL) if you track both.
- Be explicit about the Attribution window and Attribution Model (e.g., First Touch vs. Last Touch); these change CPL by channel.
Why CPL matters
CPL connects media efficiency to sales pipeline quality. A low CPL looks great—until those leads don’t convert. Pair CPL with downstream metrics such as Cost per Qualified Lead, SQL-to-Close rate, and unit economics like LTV and ROI. If LTV:CAC math breaks, a cheap CPL is still a bad buy.
CPL vs other pricing models
| Metric | Measures | Best for |
|---|---|---|
| CPC | Cost per click | Early testing, traffic scaling |
| CPL | Cost per lead | Lead gen & B2B funnels |
| CPA | Cost per final conversion | E-commerce, subscription activation |
| CPM | Cost per 1,000 impressions | Brand awareness |
Implementation tips
- Track a single, unambiguous lead event and keep it consistent across platforms.
- Use UTMs and spend imports so CPL by campaign is apples-to-apples.
- Segment CPL by channel/creative; prune anything with high CPL and weak downstream conversion.