Formulas used by this calculator
- Qualified leads needed = round up(target customers ÷ close-rate fraction)
- Incoming leads needed = round up(qualified leads needed ÷ qualification-rate fraction)
- Modeled media budget = incoming leads needed × expected cost per incoming lead
- Media cost per target customer = modeled media budget ÷ target customers
Worked example
An illustrative goal is 20 new customers, with a 20% qualified-lead close rate, a 50% qualification rate, and $40 media cost per incoming lead.
The model requires 100 qualified leads, then 200 incoming leads. Modeled media budget is 200 × $40 = $8,000, or $400 per target customer.
Each stage is rounded up separately. The rates remain assumptions, so buying that volume does not guarantee 20 customers.
Use rates from the same funnel
Define an incoming lead, a qualified lead, and a won customer before entering rates. Qualification rate uses all incoming leads as its denominator. Close rate uses qualified leads. Mixing a raw-lead close rate with these two stages would count qualification twice.
Google's conversion guidance reinforces the need to distinguish conversion actions and their reporting scope. The two-stage budgeting equations here are an original planning worksheet, not a forecast supplied by Google. Google Ads: interpreting conversion data.
Use mature outcomes and the right cost per lead
Choose rates from a cohort with enough time to qualify and close. A recent cohort with many open opportunities can make the eventual close rate appear lower than it is. Conversely, a small group of unusually strong referrals may be a poor assumption for paid traffic.
The cost input is media cost per raw incoming lead. A cost per qualified lead already includes a qualification step and should not be multiplied by the larger incoming-lead requirement. Sales labor, software, and agency expenses need a separate acquisition-cost allowance.
Check whether the business can handle the modeled demand
Translate the incoming-lead requirement into a review of response capacity, appointment slots, follow-up workload, and fulfillment. The calculator does not know whether the team can process the modeled volume or whether more spending can buy leads at the entered cost.
Run a cautious and a stronger scenario using defensible rates. Save each worksheet and state what would need to be true for it to work. Upward rounding makes the planning counts practical; it does not remove uncertainty from the acquisition process.
Common questions
Why must both rates be above zero?
A positive customer goal cannot be reached through a stage with a zero conversion rate in this model. Enter a supported positive assumption, or address the broken stage before treating the funnel as budgetable.
Can I use this as a guaranteed sales forecast?
No. Qualification, close rate, and lead cost are assumptions that can change with audience, offer, volume, and sales execution. The result is a scenario to evaluate, not a commitment from an advertising platform.