Break-even CAC calculator
before you open an ad account, you should know the highest price you can pay for a user without losing money. that ceiling is your break-even CAC. the number you should actually aim for sits well below it, because break-even is not a business, it is a stalemate.
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How to use this in an ad account
target CAC is the number you set bids and budgets against. if a campaign is coming in above it, it is not working, however good the creative looks.
break-even is the emergency line. spending between target and break-even is survivable for a short push, like a launch week, but doing it every month means you are buying revenue at cost and paying for the privilege in overheads.
The lever nobody pulls
most founders try to lower CAC. it is usually easier to raise the ceiling instead, by cutting churn. going from 10% to 7% monthly churn stretches average lifetime from 10 months to over 14, which lifts your affordable CAC by roughly 40% without touching an ad.
that is why retention work is often better value than another round of creative testing. change the churn number above and watch what happens to your ceiling.
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
Why is my target CAC so low?
usually price or churn. at $5 a month and 15% churn there is simply not much money to spend. if the ceiling comes out below what any channel can deliver, the answer is not better ads, it is a higher price, a longer commitment, or better retention.
Can I spend above break-even on purpose?
for a defined period with a defined reason, yes. buying a launch spike or defending a category before a competitor arrives can be worth it. the danger is doing it without deciding to, which is what happens when nobody has calculated this number.
Other plan tools
CAC calculator
free CAC calculator. put in your ad spend and new users, get paid CAC and blended CAC. no signup, no email.
PlanLTV 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.
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.