Free trial to paid conversion calculator
the number that catches founders out is the true cost per paying customer. if you pay $4 for a trial and only one in five converts, each paying customer cost you $20, not $4. that is the figure your unit economics need.
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The multiplier everyone forgets
your true cost per customer is the cost per trial divided by the conversion rate. at 20% conversion you are paying five times the trial cost for every customer who actually pays you.
this is why improving trial conversion is usually worth more than lowering ad costs. moving conversion from 20% to 25% cuts your real CAC by a fifth instantly, without renegotiating anything or touching a campaign.
Where trial conversion is won
in the first session, not at the end of the trial. people decide whether the product is for them long before the card is charged, and the reminder email at day 12 is arguing with a decision already made.
the practical version: get the user to the moment the product is obviously useful as fast as possible, and make sure that moment happens on day one rather than day five.
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 the trial require a card?
requiring one gives you far fewer trials at a much higher conversion rate. no card gives you volume and worse conversion. run this calculator both ways with your own numbers, because the answer genuinely differs by product and price point.
How long should a free trial be?
long enough to reach the moment the product proves itself, and no longer. if that moment happens on day one, a 30 day trial is just 29 days for the user to forget about you.
Other scale tools
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ScaleChurn to customer lifetime
convert monthly churn into how long an average customer stays, how many survive a year, and what cutting churn is worth.
ScaleK-factor calculator
work out your viral coefficient from invites sent and accepted, and see how many extra users each new user really brings.
ScaleApp store conversion
break your app store funnel into impressions, page views and installs, and find which step is leaking.
Bring one real growth problem. Leave with the fix.
the breakdown call is free. no pitch deck, no agency handoff.