No black box. Here's the exact math.
Trust comes from transparency, so here is every formula the calculator runs — the same math an accountant would do on the back of an invoice, done instantly from your five numbers.
The five things you tell it
- Average job value — revenue on a typical closed job.
- Jobs per month — paying jobs you complete in an average month.
- Close rate — of the leads you get, the share that become jobs.
- Monthly marketing spend — what you put into ads/marketing.
- Gross margin — profit on a job before marketing cost (after labor + materials).
The formulas it runs
monthly revenue = avg job value × jobs per month
leads per month = jobs per month ÷ close rate
cost per lead = marketing spend ÷ leads per month
marketing per job = marketing spend ÷ jobs per month
gross profit / job = avg job value × gross margin
net profit / customer = gross profit / job − marketing per job
monthly profit = net profit / customer × jobs per month
annual profit = monthly profit × 12
return on ad $ (ROAS) = monthly revenue ÷ marketing spend
upside = net profit / customer × extra jobs
Net profit per customer is the number that matters: what one new customer is worth to you after the work and the marketing to win them. Everything else scales from it.
The honest edges
- Zeroes, not errors. Enter 0 jobs and you get 0s, never a broken screen — the math guards every division.
- Negatives shown, not hidden. If the numbers say you're upside-down on each customer, the tool says so plainly. That's the most useful result it can give.
- Your numbers only. The result never uses our benchmarks — those appear only as context.
Where the benchmark band comes from
The cost-per-lead range ($116–$691, $219 blended) and $3.24 cost-per-click are aggregated from real Fix Scale Grow-managed Google Ads accounts over 2026-05-13 – 2026-08-10 (trailing 90 days). They're rounded and blended so no single client is identifiable, and they exist purely to help you sanity-check your own cost-per-lead — nothing more.
What we don't do
We don't promise rankings, lead volume, or income. We don't invent testimonials, review counts, or ratings. The calculator is a mirror for your own business, not a sales pitch dressed up as math.
Get your Profit Plan as a printable one-pager
Your numbers above are yours to keep. Want the detailed version — the full breakdown, your benchmark comparison, and the three highest-leverage moves for your numbers, laid out to print or send to your partner? Drop your email and it's yours.
- The full per-customer + monthly + annual breakdown
- Where your cost-per-lead sits against real managed campaigns
- A short, prioritized action list built from your inputs