The Two Numbers

The LTV:CAC Operating System

by Lech Kaniuk

The two numbers that build or break every business.

The Two Numbers is Lech Kaniuk's operating system for the two unit-economics figures that determine whether a business survives: Customer Lifetime Value (LTV) and Customer Acquisition Cost (CAC). It shows founders how to calculate them correctly, read the LTV:CAC ratio in context, and use frameworks like the LTV-CAC Growth Map and the Value Driver Framework to make sharper growth decisions. 300 pages across 15 chapters — the first four are free to read at ltvcacbook.com.