Ad Spend Calculator

Working backwards from a goal: if you know what a conversion should cost and how many you need, the required budget is a multiplication. This calculator also checks the implied cost against your revenue.

Inputs

Target conversions

Expected CPA

Revenue per conversion

Results

Required budget

$3,600.00

Expected revenue: $13,000
Expected profit before product costs: $9,400.00
Implied ROAS: 3.61×

Formula

Budget = Target Conversions × CPA

FAQ

How do I estimate CPA before running ads?

From similar past campaigns, platform benchmarks in your vertical, or from CPC ÷ conversion rate estimates. Treat it as a hypothesis to test, not a fact.

Should I budget above this number?

Usually 10–20% buffer — CPA fluctuates with competition, seasonality and creative fatigue.