What a customer costs (CAC)
CAC is every sales and marketing dollar divided by the net-new clients it won — the companies that actually wrote you a check. It is the one number that levels every decision: which channel, which hire, push or hold. Get it by channel and you will find your cheapest source is rarely your best. And when someone says a CAC is “too high,” the only honest reply is: compared to what? That answer is lifetime value.