Use this CAC calculator to measure how much it costs to acquire a new customer. Enter sales and marketing spend plus new customers acquired, then optionally estimate LTV, LTV:CAC ratio, and payback period.
Use template ->What is customer acquisition cost?
Customer acquisition cost, or CAC, measures how much a business spends to acquire one new customer over a given period. It is one of the core unit-economics metrics used in SaaS, ecommerce, consumer apps, marketplaces, and sales-led businesses because it connects growth directly to spend.
A lower CAC usually means the business is acquiring customers more efficiently, though CAC is only meaningful when viewed alongside retention, gross margin, and customer value. A business can grow quickly with a high CAC, but that only works if the revenue and margin from each customer justify the upfront cost.
CAC formula
CAC = Total acquisition spend / New customers acquired
Total acquisition spend can include paid advertising, content and SEO, sales team costs, software tools, and other channel or campaign costs tied to acquisition. The key is consistency: spend and customer counts should come from the same time period and the same scope.
How the CAC calculator works
The calculator adds together the acquisition-cost inputs you provide, then divides that total by the number of new customers acquired. That gives a clean CAC estimate for the period. It also supports optional unit-economics inputs so you can extend the analysis into LTV, LTV:CAC ratio, and payback period.
The optional LTV model uses ARPU, gross margin, and churn rate to estimate customer value, then compares that value with CAC. That helps move the conversation beyond cost alone and into efficiency. A CAC number by itself can look acceptable, but the picture changes quickly if margins are thin or churn is high.
How CAC is used in growth and finance
CAC is used to evaluate channel efficiency, sales and marketing productivity, and overall growth quality. Teams use it to compare campaigns, track changes over time, and judge whether customer growth is becoming cheaper or more expensive as a business scales.
One practical limitation: CAC depends heavily on what costs are included. Some teams include only direct paid spend, while others include salaries, tools, and overhead tied to acquisition. That means CAC is most useful when definitions are stable over time and clearly documented.