CAC Calculator

Work out what a new customer really costs, and whether your lifetime value justifies it. Get your CAC, LTV:CAC ratio, and payback period.

Enter your numbers

Acquisition
$

Everything you spent to acquire customers in the period: media, tools, and the salary or agency time behind sales & marketing.

Net-new customers won in the same period. Keep the time window consistent with your spend.

Unit economics (optional but recommended)
$

Total revenue you expect from an average customer over their lifetime. Needed for the LTV:CAC ratio.

$

Average monthly revenue per customer. Used to estimate your CAC payback period.

%

Share of revenue left after direct costs. SaaS is typically 70–90%; e-commerce is often 20–50%.

Your customer acquisition cost
$500
Healthy

Customers are worth roughly 3–5× what they cost to acquire. Growth at this ratio is sustainable.

LTV : CAC3.6 : 1
CAC payback4.2 months

Cut CAC without cutting spend

You don't have to slash budget to lower acquisition cost. Model what happens when more of the traffic and pipeline you already pay for turns into customers.

Model a lift

+5%+50%

Acquisition cost falls fastest when the funnel you already pay for converts better: same spend, more customers.

CAC today$500
CAC with the lift$417
Saved per customer$83
New LTV : CAC4.3 : 1

The cheapest customer is the one you almost had. ZipTier's AI assistant works the visitors and leads your spend already generates. It answers objections in real time and captures high-intent prospects, so more of your existing funnel becomes customers and CAC drops to $417 in this scenario.

See how ZipTier lowers CAC →

What's a good LTV:CAC ratio?

CAC on its own is just a number. It only means something next to what a customer is worth. Use these bands to judge yours.

LTV : CACRatingWhat it usually means
Under 1 : 1Losing moneyEvery new customer costs more than they'll ever return. Fix unit economics before scaling spend.
1 – 2.9 : 1Below benchmarkYou're profitable on paper but below the 3:1 rule of thumb. Margins get thin once overhead and churn bite.
3 – 5 : 1HealthyThe classic zone: customers are worth roughly 3–5× what they cost to acquire. Growth is sustainable.
Over 5 : 1Very efficientExcellent economics, though it can also mean you're underinvesting in growth and leaving market share on the table.

The 3:1 rule of thumb comes from SaaS, but the logic (a customer should be worth several times what they cost to acquire) travels well across business models. Capital-intensive or high-churn businesses need more headroom.

How CAC is calculated

Customer acquisition cost is the total amount you spend on sales and marketing over a period, divided by the number of new customers you won in that same period. It answers a simple question: what does it cost this business to create one new customer?

Formula: CAC = Total Sales & Marketing Spend ÷ New Customers Acquired
Example: $50,000 in spend ÷ 100 new customers = $500 CAC.

The important part is what you include in "spend." A fully loaded CAC counts media budgets, marketing and sales tools, agency fees, and the salaries of the people doing the acquiring, not just the ad spend. A CAC built only on media costs will always look flattering and will always mislead you.

CAC vs. CPL

They measure different stages of the funnel. Cost per lead (CPL) is what you pay for a prospect who raises their hand; CAC is what you pay for a closed customer. The two are linked by your lead-to-customer close rate: CAC = CPL ÷ close rate. A $50 CPL with a 10% close rate is a $500 CAC. If you're working further up the funnel, start with our Cost Per Lead Calculator.

What is CAC payback?

CAC payback is how many months of gross profit it takes to recoup the cost of acquiring a customer. It's the bridge between CAC and cash flow: a great LTV:CAC ratio can still strangle a business if the payback takes years. Divide CAC by monthly revenue per customer times gross margin. For example: $500 CAC ÷ ($150/month × 80% margin) = 4.2 months to break even on that customer. Under 12 months is the common target for subscription businesses.

How to reduce CAC

  1. 1

    Improve conversion before buying more traffic. Doubling your funnel’s conversion rate halves your CAC. Same result as doubling budget, at a fraction of the cost.

  2. 2

    Double down on your cheapest channels. Compute CAC per channel, not just blended. Shift budget toward the channels that produce customers, not just clicks.

  3. 3

    Fix speed-to-lead. Leads that get a response in minutes close at multiples of the rate of leads that wait a day. Faster follow-up means more customers from the same spend.

  4. 4

    Lean into referrals and word of mouth. Customers acquired through referrals typically carry near-zero incremental cost and churn less, so every one drags your blended CAC down.

  5. ★

    Convert the funnel you already pay for. An AI assistant like ZipTier works the visitors and leads your existing spend generates. It answers questions on the spot, handles objections, and captures high-intent prospects, so more of them become customers and your CAC falls without touching the budget.

Frequently asked questions

What should I include in acquisition spend?
Everything sales and marketing costs you: media and ad spend, marketing and sales software, agency and contractor fees, content production, events, and the salaries of your sales and marketing teams. If a cost exists to win new customers, it belongs in the numerator. Leaving out salaries and tools is the most common way companies understate their real CAC.
Should CAC be blended or paid-only?
Compute both. Blended CAC (all spend ÷ all new customers) tells you whether the business as a whole acquires customers profitably. Paid CAC (paid spend ÷ customers from paid channels) tells you whether a specific channel deserves more or less budget. Use blended for overall health and board reporting; use paid-only for channel decisions.
What's a good LTV:CAC ratio?
The common benchmark is 3:1: a customer should be worth about three times what they cost to acquire. Below 1:1 you lose money on every customer; between 1:1 and 3:1 margins are usually too thin once overhead and churn are counted; well above 5:1 often means you could grow faster by spending more. The right target also depends on margins, churn, and how capital-intensive your business is.
How can I lower CAC without cutting budget?
Convert more of the demand you already pay for. Most funnels lose the majority of visitors and leads before a sales conversation ever happens. An AI assistant like ZipTier works those prospects in real time. It answers questions, handles objections, and captures contact details, so the same spend produces more customers. Because CAC is spend divided by customers, growing the denominator cuts CAC just as surely as cutting the numerator, without shrinking your pipeline.

Acquire more customers from the spend you already have

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