What is customer acquisition cost?

Customer acquisition cost is what you spend, on average, to win one new customer. It bundles the sales and marketing costs of a period — media, agency fees, salaries, tooling — and spreads them across the new customers won in that period. It is the single most direct measure of how efficiently a growth budget is working.

How do you calculate customer acquisition cost?

CAC = total sales and marketing spend ÷ new customers acquired. Spend $8,000 in a month and win 160 new customers, and your CAC is $50. Use the same period for both figures, and count only genuinely new customers in the divisor.

There is no absolute answer, and published industry averages are a poor substitute: the spread between B2B software and ecommerce runs to a factor of twenty. Two relative limits are usable. Your CAC should sit below your contribution margin per order, otherwise you lose money on the first purchase, and below a third of your profit CLV, which is the same as an LTV:CAC ratio of 3:1.

Is a lower CAC always better?

A low CAC is generally good, but the absolute figure says little on its own. What matters is the ratio to lifetime value: a $50 CAC is excellent against a high CLV and ruinous against a low one. Three to one or better counts as healthy, so a higher CAC can be entirely rational when the customers are worth proportionally more.

Customer Acquisition Cost Calculator

What one new customer costs you, and whether that price is one your lifetime value can carry.

Sales and marketing spend ($) Everything spent on winning customers New customers won Acquired in the same period

Customer acquisition cost

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spend ÷ new customers

Average CLV ($) (optional)

The gross profit a customer brings across the whole relationship. The calculator holds it against your acquisition cost as a ratio.

→ Calculate it

Unlocks the LTV:CAC verdict below.

LTV:CAC ratio —

LTV:CAC verdict

0:1 1:1 2:1 3:1 ≥5:1

< 1:1 Loss-making 3:1 Healthy > 4:1 Excellent

CAC sensitivity

CAC at double the customers

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same spend, twice the conversions

The curve assumes spend stays flat. In practice your conversion rate shifts as you scale, so read the chart as orientation rather than forecast.

Marketing cost per customer: what belongs in the number

The customer acquisition cost is what you spend, on average, to win one new customer — and the word «marketing» in it is narrower than the metric. The convention counts sales and marketing together: media budget, agency fees, the salaries of the people doing the acquiring, tooling. Leave the unglamorous half out and the figure comes back flattering and useless. On its own it still decides nothing; only against the customer lifetime value does it become a verdict, and the LTV:CAC ratio is where that verdict lives. The working rule: lifetime value should clear acquisition cost by three times or more.

CAC = total sales and marketing spend ÷ new customers acquired

CPA calculator or CAC calculator? The difference is the divisor

Both divide spend by a count, and that count is the whole distinction: a CPA divides by conversions, a CAC by new customers. Since a conversion can be a repeat buyer, a lead or a signup, the two only agree when every conversion is a first-time customer. This calculator divides by new customers. A shop spending $4,800 on performance marketing in a quarter and winning 80 of them:

Total spend$4,800

New customers won80

CAC = 4,800 ÷ 80 = $60

A $60 acquisition cost works if the profit CLV is at least $180 — that is the LTV:CAC ratio at 3:1. Count the same 80 orders as conversions while a fifth of them were returning buyers, and the per-conversion figure reads $60 while the true cost per new customer is closer to $75.

What an average CAC tells you, and what it hides

Published averages are the most-searched thing about this metric and the least useful. They mix business models that have nothing in common — a subscription sold to enterprises and a $30 impulse purchase both appear as one «average», and any combined figure across industries describes no company at all. Two relative limits do the work instead: your contribution margin per order, above which you lose money on the first purchase, and the ratio to your profit CLV.

CAC < contribution margin per order profitable from the first sale

CAC < profit CLV ÷ 3 healthy enough to scale (3:1)

CAC > profit CLV structural loss

The spread between B2B software and ecommerce runs to a factor of twenty, which is why an industry number makes a poor target even when it is measured honestly. What survives the comparison is your own contribution margin and LTV:CAC.

Bringing CAC down: cheaper traffic or a better funnel

Shift the channel mix: moving budget from expensive placements towards search or referral often takes 30–50 % out of the cost, because the price of attention differs far more between channels than within them.
Convert more of the traffic you already pay for: every point of conversion rate cuts the cost proportionally at no extra spend — the cheapest lever there is. Work out where you stand with the conversion rate calculator.

Frequently asked questions

What is customer acquisition cost?: Customer acquisition cost is what you spend, on average, to win one new customer. It bundles the sales and marketing costs of a period — media, agency fees, salaries, tooling — and spreads them across the new customers won in that period. It is the single most direct measure of how efficiently a growth budget is working.
How do you calculate customer acquisition cost?: CAC = total sales and marketing spend ÷ new customers acquired. Spend $8,000 in a month and win 160 new customers, and your CAC is $50. Use the same period for both figures, and count only genuinely new customers in the divisor.
What is a good CAC?: There is no absolute answer, and published industry averages are a poor substitute: the spread between B2B software and ecommerce runs to a factor of twenty. Two relative limits are usable. Your CAC should sit below your contribution margin per order, otherwise you lose money on the first purchase, and below a third of your profit CLV, which is the same as an LTV:CAC ratio of 3:1.
Is a lower CAC always better?: A low CAC is generally good, but the absolute figure says little on its own. What matters is the ratio to lifetime value: a $50 CAC is excellent against a high CLV and ruinous against a low one. Three to one or better counts as healthy, so a higher CAC can be entirely rational when the customers are worth proportionally more.