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CAC calculator.

Find out what a new customer costs you, how many months they take to pay that back, and whether their lifetime value justifies it.

Free · Runs in your browser · Formulas shown

One period of spend

A month or a quarter; use the same period for both spend and customers.

$

Ads, content, sponsorships, agencies and marketing salaries.

$

Sales salaries and commissions.

$

CRM, email and analytics tools used to acquire.

Paying customers won in the same period.

For payback and LTV:CAC

$/mo
%
%

Building a SaaS?

Each new customer costs you $400 and pays that back in 10 months. SyntaxKit is a Next.js starter kit with sign-in, payments and teams built in, so you reach your first paying customer sooner.

Customer acquisition cost

$400

$10,000 spent to win 25 customers.

Total acquisition spend
$10,000
CAC payback
10 months
Customer lifetime value
$1,333
LTV:CAC
3.3:1
  • Payback: Within the common 12-month target.
  • Healthy: at or above the common 3:1 target.
The math

How customer acquisition cost is calculated.

CAC is acquisition spend divided by the customers it produced, measured over the same period. The examples below use your numbers from the calculator.
Customer acquisition cost

CAC = (marketing + sales + tools) ÷ new customers

($6,000 + $3,000 + $1,000) ÷ 25 = $400
CAC payback

CAC payback in months = CAC ÷ (ARPA × gross margin)

$400 ÷ ($50 × 80%) = 10 months

Under 12 months is the common target.

Customer lifetime value

LTV = ARPA × gross margin ÷ monthly churn

$40 ÷ 3% = $1,333
LTV to CAC ratio

LTV:CAC = LTV ÷ CAC

$1,333 ÷ $400 = 3.3:1

3:1 or higher is the common target.

With long sales cycles, compare this quarter's customers with last quarter's spend, since that is the money that won them. For the LTV side of the ratio, the LTV calculator adds a discount rate and handles 0% churn.

Benchmarks

What good looks like.

Rules of thumb from published SaaS research.
SaaS benchmarks and their sources
MetricBenchmarkSource
CAC paybackUnder 12 monthsDavid Skok, SaaS Metrics 2.0
CAC payback, reportedAbout 10 months (smaller ARR) to 15 months (larger ARR)OpenView 2023 SaaS benchmarks
LTV:CAC3:1 or higherDavid Skok, SaaS Metrics 2.0
New CAC ratioMedian $2.00 of sales and marketing per $1 of new ARRBenchmarkit 2025 SaaS benchmarks
FAQ

CAC questions.

How do you calculate customer acquisition cost?

Add up everything you spent on sales and marketing in a period and divide by the new customers you won in that period. $10,000 of spend and 25 new customers is a CAC of $400.

What costs should be included in CAC?

Everything spent to win customers: ad spend, content and sponsorships, agencies, the salaries and commissions of sales and marketing staff, and the tools they use. Leaving salaries out gives a 'paid CAC' that looks far cheaper than reality.

What is the difference between blended CAC and paid CAC?

Blended CAC divides all acquisition spend by all new customers, including those who found you organically. Paid CAC divides only paid media spend by customers from paid channels. Paid CAC is always lower; don't compare one against the other's benchmark.

How do you calculate CAC payback?

Divide CAC by the monthly gross profit from one customer: CAC / (ARPA × gross margin). A $400 CAC with $50 ARPA and 80% margin pays back in 10 months.

What is a good CAC payback period?

Under 12 months is the usual target. OpenView's 2023 benchmarks put the reported median at about 10 months for smaller companies and 15 for larger ones, where sales cycles are longer.

What is a good LTV to CAC ratio?

3:1 or better. Below that, each customer barely earns back what they cost once you include the cost of serving them.

What if I won zero new customers this period?

CAC is undefined, because you'd be dividing by zero. Use a longer period, such as a quarter, so the spend and the customers it produced line up.

Should I count my own time in CAC?

If you do the selling or marketing yourself, add what you'd pay someone else to do it. A founder-led CAC of zero looks great until you hire the first marketer.

SyntaxKit

Spend your time on the product, not the plumbing.

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  • Analytics, email and rate limiting
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