Business Math
CAC Calculator
Divide sales and marketing spend by new customers acquired.
Inputs
Change values
Related
Related tools
API example
Use this tool from code.
API access is free during beta, no key required, and rate-limited for reliability.
Request
POST endpoint
POST /api/tools/cac-calculator
Content-Type: application/json
{
"inputs": {
"spend": 12000,
"customers": 180
}
}Response
Example output
{
"tool": "cac-calculator",
"result": {
"summary": "CAC: $66.67 per customer.",
"outputs": [
{
"label": "CAC",
"value": "$66.67"
},
{
"label": "Customers",
"value": "180"
},
{
"label": "Spend",
"value": "$12,000.00"
}
]
}
}About this tool
CAC Calculator guide
How to use the CAC Calculator
Divide sales and marketing spend by new customers acquired. Use this business calculator when you need to estimate an operating metric or business tradeoff without building a spreadsheet from scratch. Enter realistic values for sales and marketing spend, new customers, then run the tool and compare the output against the decision you are trying to make. The example starts with sales and marketing spend of 12000, new customers of 180, but the stronger workflow is to change one input at a time so you can see which assumption actually drives the result.
What the result means
The output is a planning estimate for operators, founders, marketers, and analysts. It helps turn revenue, cost, customer, ad, margin, or runway assumptions into a clear metric, but it is not a replacement for bookkeeping, accounting, or source-of-truth reporting. The useful signal is often not just the headline number; it is how much that number changes when one input moves. If the result is fragile, document the assumption and rerun the calculator with a conservative case before using it in a plan, report, trade, launch, or implementation decision.
When to use this business tool
Use it during campaign planning, pricing work, investor updates, funnel reviews, budget reviews, support planning, or quick board-style metric checks. It is useful when you need to understand whether a change in spend, conversion, churn, price, or volume is large enough to matter. This page fits searches such as cac calculator, customer acquisition cost, startup metrics because it keeps the fields visible, loads a working example, and returns copy-ready output without sign-up. Use the result to tighten your next question, narrow a range, or decide whether a more detailed model is worth building.
Common mistakes to avoid
Do not mix time periods, gross and net numbers, one-time and recurring revenue, or cash and accrual accounting without labeling the assumptions. Compare optimistic, expected, and conservative cases so one appealing scenario does not hide weak unit economics. Keep the input assumptions with the output so the number is explainable later. A clean result with hidden assumptions is worse than a rough result with clear assumptions, because nobody can audit what changed when the real-world numbers move.
How to verify the output
Confirm important decisions against your analytics, accounting system, CRM, ad platform, payment processor, or finance model. If the result will influence money, production systems, customer promises, or public claims, rerun it with cautious values and check the relevant source data. Good utility tools speed up judgment; they should not hide the judgment step.
FAQ
Questions about this tool
Is this business metric exact?
No. It is a deterministic estimate based on the values you enter. Real-world systems, providers, markets, and reporting tools may use different rules or fresher data.
Which input should I adjust first?
Start with sales and marketing spend, then change new customers. Moving one input at a time makes it easier to see which assumption has the largest effect on the output.
Can I use this result for an important decision?
Use it for planning and comparison. Confirm board-level, tax, accounting, payroll, hiring, or budget decisions with your source-of-truth systems and advisors.
Why does my result differ from another tool?
Different tools may round differently, include different assumptions, or use a different source of truth. Compare the inputs and definitions before comparing the final number.