CAC Calculator

Customer acquisition cost (CAC) is the average spend required to win one new paying customer. It combines sales and marketing effort — ads, agency fees, sales salaries, tools, and campaign production — divided by the number of customers acquired in the same period.

CAC on its own is incomplete. A £200 CAC is fine if each customer is worth £2,000 over their lifetime; it is unsustainable if they churn after one small purchase. Always compare CAC with lifetime value (LTV).

Track CAC by channel when possible. Blended CAC hides efficient and wasteful spend sitting in the same average. Use the channel CAC and blended CAC calculator when you need to compare paid, organic, sales, and partner acquisition side by side.

Customer acquisition cost (CAC) is average spend to win one new paying customer. CAC = total acquisition spend ÷ new customers in the period.

Blended CAC hides channel efficiency — segment paid vs organic when possible.

Compare with channel CAC blended CAC, LTV calculator, and LTV vs CAC breakeven calculator.

Spend £2,000 on sales and £5,000 on marketing — £7,000 total — to acquire 120 customers. CAC = £7,000 ÷ 120 = £58.33 per customer (rounded).

If the same spend only yields 80 customers, CAC rises to £87.50. Conversion and funnel efficiency directly move CAC without any change in ad budget.

Many SaaS businesses aim for LTV at least 3× CAC. At £58 CAC, that implies roughly £174 lifetime gross margin as a minimum economic hurdle — before overheads.

Acquisition spend £24,000, 120 new customers → CAC = £200 per customer.

If spend rises to £30,000 at same customers, CAC = £250 — 25% worse unit economics.

If customers rise to 150 at £24,000, CAC = £160 — efficiency improved.

Improve conversion rate so more leads become customers from the same spend. Sharpen targeting to waste less budget on poor-fit traffic. Increase referral and organic share so paid spend is a smaller part of the mix.

Include fully loaded costs — sales commissions, creative production, and software — or CAC will look artificially low.

CAC = (marketing + sales + related onboarding cost) ÷ new customers acquired.

Use the same period for spend and customer count — monthly CAC needs monthly spend and monthly new logos.

Exclude retention-only spend from CAC unless it wins reactivated churned users counted as new.

Before scaling ad budget or hiring sales.

When conversion rates shift after pricing or product changes.

Quarterly for board or investor reporting.

Improve conversion on same traffic.

Better targeting to reduce wasted spend.

Product-led growth to supplement paid.

Referrals and partnerships.

Fix onboarding drop-off after signup.

Blended CAC of £180 can mask paid search at £320 and referrals at £40. Scaling spend on the blended number alone burns cash if the marginal customer comes from expensive channels.

Align the measurement window — ad spend in March may produce customers in April. Match spend period to conversion lag or use cohort-based CAC for board reporting.

Compare CAC to LTV calculator on the same gross-margin basis you use for payback — mixing net LTV with gross-margin CAC payback breaks unit economics.

Blended CAC of £120 can mask £280 paid search and £45 referral — scaling spend on the average destroys unit economics while referral remains under-invested.

Calculate CAC by channel, campaign, and cohort month with the channel CAC blended CAC calculator — payback and LTV calculator inputs should use the same segment, not company-wide averages.

Including brand campaigns and content with multi-year payback in the same numerator as performance marketing — segment or amortise brand spend separately.

Counting reactivated churned users as new customers while using full acquisition spend in the denominator — align definitions with finance.

Ignoring sales discounts and onboarding credits given to win the logo — they are part of acquisition cost even if not in the ad platform dashboard.

Review CAC by channel monthly — pause channels above your LTV-based ceiling even if blended CAC looks acceptable.

When CAC spikes, check conversion rate and sales cycle length before blaming ad creative alone.

Update LTV calculator assumptions in the same meeting so acquisition targets stay paired with retention reality.

This page should target CAC calculator, customer acquisition cost calculator, marketing CAC, sales CAC, and acquisition cost per customer searches.

It calculates CAC from sales spend, marketing spend, and customers acquired. It does not import ad-platform spend, split paid and organic channels automatically, amortise brand spend, handle sales-cycle lag, calculate payback, or model LTV by itself. Use channel CAC blended CAC when channel segmentation is the actual question.