Practical guide
Blended CAC vs channel CAC: avoid averaging ratios
Compare paid and organic acquisition with customer-weighted CAC and a worked channel-mix example.
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How should channel CAC values be combined?
Add the costs and add the acquired customers, then divide the totals. Do not take an unweighted average of channel CAC values unless the channels acquired exactly the same number of customers.
A channel-mix example
In an illustrative quarter, paid search costs $40,000 and brings 100 customers. A content program costs $20,000 and brings 200 customers. Paid-search CAC is $400; content CAC is $100. The blended result is $60,000 ÷ 300 = $200, rather than the simple average of $250.
Enter the combined spending and combined new customers in the calculator. Run each channel separately if you also want the individual values. Preserve the attribution method so a customer influenced by both channels is not counted twice.
What happens when the mix changes?
Suppose paid search brings 200 customers at the same $400 CAC, while content still brings 200 at $100. Total cost is now $100,000 for 400 customers, giving blended CAC of $250.
Neither channel became less efficient. The blend rose because more customers came from the higher-cost channel. That distinction matters when reviewing a growth plan: the team may have expanded acquisition capacity without changing either channel’s unit economics.
A useful report shows each channel’s cost, customer count, CAC, and share of new customers. The overall ratio then has an explanation that can be checked against the underlying data.
Channel CAC questions
Is organic acquisition free?
Not necessarily. If the report includes content production, staff, and tools, those costs belong in the relevant acquisition scope. Keep cash spending and allocated internal cost definitions clear.
Should the cheapest channel get the whole budget?
This calculator does not estimate how acquisition efficiency changes at larger spend or whether customers retain equally well. Compare lifetime value and acquisition capacity separately. A channel with a low observed CAC may be small, slow, or attract a different customer group; the historical ratio alone cannot resolve that decision.
Use the cac calculator to reproduce the scenario with your own inputs.