Free marketing & patients tool
Customer Acquisition Cost (CAC) Calculator
Customer acquisition cost (CAC) is what you spend to win one new patient: total marketing spend divided by new patients. Cost per lead divides the same spend by leads. If you spend $5,000 and get 80 leads, 36 consults and 18 new patients, cost per lead is $62.50 and CAC is $277.78. Enter your own funnel below to see every step.
Prepared by Prospyr · Reviewed October 3, 2026 · Free, no sign-up, runs in your browser
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Customer acquisition cost (cost per new patient)
$277.78
$5,000 spent for 18 new patients.
Cost per lead
$62.50
$5,000 ÷ 80
Cost per consult held
$138.89
$5,000 ÷ 36
Lead to consult
45%
Consult to patient
50%
CAC, cost per lead and cost per acquisition formulas
- Cost per lead (CPL): total spend ÷ leads
- Cost per consult held: total spend ÷ consults held
- CAC / cost per acquisition (CPA): total spend ÷ new patients
- Funnel rates: consults ÷ leads, new patients ÷ consults, new patients ÷ leads
- Goal planner: leads needed = goal patients ÷ lead-to-patient rate, rounded up
A good lead cost can hide a weak funnel. A $30 lead sounds cheap until only one in ten books and shows. That is why the calculator prints cost and rate at every step, not just the last one.
Worked example: from spend to cost per new patient
| Stage | Count | Cost at this stage | Rate from the step before |
|---|---|---|---|
| Spend ($4,000 ads + $1,000 other) | $5,000 | – | – |
| Leads | 80 | $62.50 | – |
| Consults held | 36 | $138.89 | 45% |
| New patients | 18 | $277.78 | 50% |
With a $900 first visit at 60% gross margin, the first visit earns $540, so it covers the $277.78 CAC with $262.22 to spare. For a goal of 30 new patients at the same rates, you need about 134 leads, 60 consults and $8,333 of spend.
What to do with the number
Compare CAC with what a patient is worth over time using the patient lifetime value calculator. If you run paid ads, the ROAS calculator shows whether the ad revenue covers its cost, and the conversion rate calculator shows which funnel step to fix first.
Lead-to-consult is often the weakest step because slow replies lose people. Letting patients book themselves with online scheduling removes one step between a lead and a consult.
Frequently asked questions
How do you calculate customer acquisition cost?
Add up what you spent on marketing in a period and divide by the number of new patients you gained in that period. $5,000 of spend and 18 new patients is a CAC of $277.78. Count every cost that exists to win patients, including ad spend, agency fees, tools and marketing staff time, so the number is not flattered.
What is the difference between cost per lead and cost per acquisition?
Cost per lead (CPL) divides spend by leads such as calls, form fills and messages. Cost per acquisition (CPA) divides the same spend by patients who actually paid for a first visit. CPA is always higher than CPL, and the gap between them is your funnel: the fewer leads that book and show, the larger it is.
How do I calculate CPA in a practice?
Use the same formula, spend divided by new patients, and define the conversion as a paid first visit rather than a booking. A booking that no-shows is not an acquisition. The calculator also shows cost per consult held, which is the best middle-of-funnel number to watch.
Which costs should go into CAC?
Include everything you would stop spending if you stopped acquiring patients: ads, agency or freelancer fees, SEO and landing-page tools, promotional discounts you choose to track, and the share of a coordinator's time spent on leads. Leave out the cost of treating the patient. Use the same list every month so the trend is reliable.
What is a good CAC?
There is no universal number. A good CAC is one that the patient's lifetime gross profit clearly exceeds, and that you earn back fast enough for your cash flow. The calculator compares CAC with first-visit profit, and you can take the number to the patient lifetime value calculator for the full comparison.
How do I lower my acquisition cost?
CAC falls when spend per lead falls or when more leads turn into patients. Enter a better lead-to-consult or consult-to-patient rate in the conversion rate calculator and see what it does. Faster follow-up and reminders often move consult show rates without any extra ad spend.
Sources and scope
- Gupta S, et al. Modeling Customer Lifetime Value. Journal of Service Research, 2006;9(2):139-155
Peer-reviewed. Frames marketing spend as an allocation between acquiring, retaining and cross-selling customers, which is how CAC is judged against lifetime value.
- Gallo A. The Value of Keeping the Right Customers. Harvard Business Review, October 29, 2014
Reports that acquiring a new customer can cost anywhere from five to 25 times more than retaining one.
- About Conversion rate. Google Ads Help
Google's definition of conversion rate as conversions divided by ad interactions, with a 50 of 1,000 equals 5% example.
Planning math from the numbers you enter. Results are only as good as your lead, consult and patient counts, and they are not financial advice.