CPA-to-CAC Scalability Matrix
Model how CPA inflates as you double and triple spend — budgets never scale linearly.
$
$
%
How much CPA rises each time you double budget.CAC at current spend
$120
417 customers/mo
CAC at 2× spend
$142
706 customers/mo
CAC at 3× spend
$156
Blended acquisition cost
CAC premium at 3×
30.0%
vs. today
Tripling spend doesn't triple customers — at 18% decay your CAC climbs to $156 (30% higher). Check that number against LTV before you scale.
Decay compounds per doubling of spend, so returns bend as you exhaust your best audiences and placements first.
About this calculator
Apply a decay factor to your current CPA to project blended acquisition cost at 2× and 3× spend, so you can see where scaling breaks your unit economics.
Everything runs in your browser — nothing you type is sent anywhere or stored. Use it to sanity-check a plan, pressure-test a channel, or brief a team before you commit budget.