CAC calculator
CAC is what it costs you to get one new user. paid CAC counts only the users your ads brought. blended CAC divides the same spend across everyone who arrived, including the ones who came free. founders quote blended when they want the number to look good, so know which one you are looking at.
this calculator needs javascript. the explanation below works without it.
How CAC is calculated
paid CAC is total acquisition spend divided by the users that spend brought in. blended CAC is the same spend divided by every new user in the period, however they arrived.
the gap between the two is the interesting part. if your blended CAC is far below your paid CAC, most of your growth is organic and your ads are doing less than the headline suggests. that is fine, as long as you know it.
What to do with the number
CAC on its own means nothing. it only becomes useful next to lifetime value, because the question is never "is this cheap" but "do I earn it back, and how fast". check it against the LTV to CAC calculator.
a warning worth repeating: do not include salaries in CAC unless you also do so consistently every month. mixing definitions between months is the most common way founders convince themselves growth is improving when it is not.
Numbers tell you what. They do not tell you what to do.
bring your real numbers to the breakdown call and leave with a plan for them. free, no pitch deck.
Common questions
Should I include salaries in CAC?
you can, and some investors will ask you to, but be consistent. pick one definition and keep it for every month you report. the number is for comparing periods against each other, and that only works if the definition holds still.
Is a $0.02 CAC realistic?
that was ZuAI blended, over a long run, in a market with cheap inventory and heavy organic pull from UGC. it is real but it is not a benchmark for you. your own CAC depends on your category, country and price point, and comparing yourself to someone else's number is mostly a way to feel bad.
Other plan tools
LTV calculator
free lifetime value calculator. put in price, margin and churn, get LTV and how long an average user stays. no signup.
PlanLTV:CAC and payback
free LTV:CAC calculator with payback period. find out if your unit economics work and how many months to earn a user back.
PlanBreak-even CAC
work out the most you can afford to pay for a user before you lose money, and the target CAC that leaves healthy margin.
PlanRunway and burn
free runway calculator. cash, burn, revenue and planned hires in, months of runway out, with and without the hires.
Bring one real growth problem. Leave with the fix.
the breakdown call is free. no pitch deck, no agency handoff.