Calculate it properly: the profit-true CLV formula
Most lifetime-value calculations flatter you, because they use revenue where they should use margin. If you are going to steer by this number, you need a version that tells the truth, and the truth is built on what you actually keep.
The formula
The profit-true customer lifetime value formula is straightforward: CLV equals ARPA multiplied by gross margin percentage, divided by churn rate. ARPA is your average revenue per account in the period. Gross margin strips out the cost of actually serving that customer. Churn rate is the share of that revenue you lose each period. The whole thing reads as the per-period profit a customer generates, divided by the rate at which customers leave, which gives you the total profit you can expect across the relationship.
Why margin, not revenue, is the load-bearing word
The reason to insist on gross margin rather than top-line revenue is that a chunk of every 'lifetime' euro was never yours to begin with. B2B gross margins typically run 70% to 85%, which means at a 75% margin a full quarter of the revenue a customer pays you goes straight back out to serve them. A lifetime-value number built on revenue overstates your real economics by exactly that gap, and it overstates it most for the customers who are most expensive to serve, which is precisely where you least want to be deceived. Use margin and the number becomes a decision you can trust.
A worked example you can feel
Take a solo B2B SaaS founder running at 95% gross margin, 100 EUR ARPA per month, and 3% monthly churn. The CLV is (100 multiplied by 0.95) divided by 0.03, which lands at roughly 3,170 EUR per customer. Now cut churn from 3% to 2% and nothing else. The CLV climbs to roughly 4,750 EUR, a 50% jump in lifetime value from a single point of churn, with no new customers won and no price changed. That is the leverage hiding inside the denominator, and it is why the retention dial is so powerful: churn sits on the bottom of the fraction, so small improvements there move the whole number hard.
Plug in your own three numbers
The whole formula reduces to three inputs you can pull today: your ARPA, your gross margin, and your churn. Drop them in, read your CLV, and then run the same calculation with each dial nudged one notch better to see which one moves your number most. That sensitivity test is the single most clarifying exercise in this playbook, because it tells you where your leverage actually lives rather than where you assume it does.
Graduate to cohort LTV when you have the data
The single-snapshot formula is the right place to start, but it has a known weakness: it assumes a constant churn rate, when real retention curves bend. Customers churn fastest early and then settle, so a formula fed a single churn number will systematically over- or under-state lifetime depending on where your cohort sits on its decay curve. Once you have at least twelve months of data, graduate from the formula to cohort LTV, projecting lifetime from the real retention curve of each signup month. The formula steers you while you are young; the cohort curves steer you once you have a base worth measuring.