Metric
Customer acquisition cost is what you pay, all in, to win one customer. It's the number that decides whether paid growth is a machine or a leak — and the only way to judge it is against what a customer is worth.
CAC = total sales & marketing spend ÷ new customers. Spend $10,000 in a month and acquire 200 customers, and your CAC is $50. A fully-loaded CAC includes ad spend, tools, and the people running it — not just the media bill.
CAC means nothing alone. Pair it with lifetime value to get the ratio that matters. The rule of thumb is LTV:CAC ≈ 3:1 — earn about three dollars for every one you spend acquiring. Below 1:1 you're losing money per customer; well above 3:1 often means you could afford to spend more and grow faster.
Inside your ad platform, CAC is driven by CPA, which is CPC divided by conversion rate. Every improvement in click cost or conversion flows up into a lower CAC — and the creative touches both.
Better creative wins cheaper impressions and more qualified clicks, pulling CAC down without touching your bids or audiences. The catch is that you normally only learn a creative's CAC after spending behind it. Predicting whether an ad holds attention first lets you scale the winners and starve the losers. See ad pre-testing and ROAS.
Score your ads for attention before you spend behind them. First analysis free.
Score Your AdCAC — customer acquisition cost — is the total sales and marketing spend needed to win one new customer. If you spend $10,000 to acquire 200 customers, your CAC is $50. It's the headline efficiency number for any business that buys growth.
A good CAC is judged against lifetime value, not in isolation. The common healthy target is an LTV:CAC ratio of about 3:1 — a customer worth three times what they cost to acquire. Below 1:1 you lose money on every customer; far above 3:1 can mean you're underspending on growth.
CPA usually measures the cost of a single conversion action within one campaign; CAC is the fully-loaded cost of acquiring a paying customer across all sales and marketing. CAC is the broader business metric; CPA is the ad-account one.