Audited —·Last updated 29 Jul 2026·6 citations·Tier 1·0 uses

CAC Calculator — Customer Acquisition Cost

Free customer acquisition cost calculator. Work out CAC on a blended or paid-only basis, with the numerator and denominator shown beside the answer.

CAC Calculator

Which CAC do you want?
Everything you can attribute to paid acquisition for the period: media and ad spend, agency fees, affiliate and referral bounties, acquisition discounts and credits, and the loaded cost of salespeople who work only paid leads.
$
Acquisition cost you cannot attribute to a paid channel: brand and content marketing, PR, events, marketing tooling, and sales headcount that works inbound. Bessemer also puts the sales-linked share of customer success here; the plain S&M line item does not.
$
Customers, not signups, trials, leads or conversions. Count only those who started paying in this period and were attributed to a paid channel.
New paying customers in the same period with no paid attribution — word of mouth, direct, SEO, referrals from existing users. Leave at 0 if you cannot separate them; blended CAC then equals paid CAC.
Customer acquisition cost
$150.00
Acquisition cost per new customer on the basis you chose. CAC has no single standard definition — always state which costs and which channels you included.
Numerator used
$60,000.00
Denominator used
400
Total acquisition spend
$60,000.00
Total new customers
400
Organic share of customers
37.50%
Basis
Blended basis — all spend ÷ all new customers

Background.

Customer acquisition cost is the amount of sales and marketing money a business spends to win one new customer. It is the denominator of almost every unit-economics question a founder, board or investor asks — is growth worth buying, how long until a customer pays for itself, and how much of the next funding round should go into the go-to-market engine rather than into product. This calculator returns CAC on either of the two bases that the primary practitioner sources actually name, and it shows you the numerator and the denominator it divided, so the number is never a black box.

The first thing to understand about CAC is that there is no authority that defines it. No accounting standard sets it, no regulator prescribes it, and the three most-cited practitioner sources scope it differently. David Skok's SaaS Metrics definitions give the narrow version — sales and marketing expenses divided by new customers acquired. Andreessen Horowitz's 16 Startup Metrics gives a wider one, calling CAC "the full cost of acquiring users, stated on a per user basis" and insisting that referral fees, credits and acquisition discounts be included even though those sit in contra-revenue rather than in the S&M line. Bessemer Venture Partners goes wider still: in Scaling to $100 Million they describe sales and marketing as capturing "sales expenses, sales compensation, content and brand marketing, demand generation, and customer success expenses related to sales." The same company, honestly reporting under all three, will publish three different CACs. That is why this page asks you to fill the numerator yourself and then prints it back to you.

The second thing is the split between blended and paid. Blended CAC divides everything you spent by everyone you won, including the customers who arrived through word of mouth and cost you nothing at the margin. Paid CAC divides paid-channel spend by paid-channel customers. a16z's own illustration makes the gap concrete: if half your users cost $100 each through paid marketing and the other half arrive free, paid CAC is $100 while blended CAC is $50 — the same business, two numbers, one of which is twice the other. Investors weight paid CAC more heavily because it is the number that tells you whether you can pour more money in and get more customers out. But blended is not automatically the flattering one. In the worked example below, blended CAC is $150 and paid CAC is $160, because 150 organic customers dilute the denominator faster than $20,000 of brand spend inflates the numerator. Change that to $20,000 of brand spend producing only 20 organic customers and blended climbs to $222.22, above paid. Neither basis is reliably lower; you have to compute both.

The third thing is what CAC is actually for. On its own it means very little — $150 is excellent for an enterprise contract and catastrophic for a $9-a-month consumer app. CAC only becomes a decision when you divide it into lifetime value or into monthly gross profit, which is why this page links to the LTV:CAC ratio and CAC payback calculators. It is also worth knowing how much leverage the metric really carries. Gupta, Lehmann and Stuart's 2004 Journal of Marketing Research study of five firms found that a 1% improvement in acquisition cost lifted customer value by only 0.02% to 0.3%, while a 1% improvement in retention lifted it by 2.45% to 6.75%. Cutting CAC is real work with small returns; keeping the customers you already bought is the same work with an order of magnitude more payoff.

Finally, a limitation that belongs beside the number rather than buried below it: CAC will not tie to any line on your income statement. Under FASB ASC 340-40, incremental costs of obtaining a contract — a sales commission is the textbook case — are capitalised as an asset when the entity expects to recover them, then amortised as the customer is served. CAC does the opposite, charging the whole cost against the period in which the customer was won. Both are correct for their own purpose, but a reader who reconciles your CAC to GAAP sales and marketing expense will not find agreement. If you publish the metric, SEC Release 33-10751 is the standard to hold yourself to: give a clear definition of the metric and how it is calculated, say why it is useful and how management uses it, and disclose it if you change the calculation between periods.

What is cac calculator?

Customer acquisition cost (CAC) is total acquisition spend for a period divided by the number of new customers acquired in that period. It is a per-customer average, not a marginal cost: the next customer may cost far more than the last, which is why a16z notes it might cost $1 to acquire your first 1,000 users, $2 for the next 10,000, and $5 to $10 for the next 100,000. Two bases are in common use. Blended CAC uses all acquisition spend over all new customers from every channel; paid CAC uses paid-channel spend over the customers that paid channels produced. CAC is not a GAAP measure and no standards body defines it — the scope of the numerator varies materially between the leading practitioner definitions, and the choice of denominator (customers, not signups, trials, leads or ad conversions) varies too. CAC is closely related to but distinct from CPA, cost per acquisition, which ad platforms report per campaign for whatever conversion event you configured; a CPA conversion is often a lead or a trial, not a paying customer, so CPA is usually much lower than CAC and the two should never be compared directly. CAC is a period metric — it describes a cohort you already bought — and it is most useful as an input to the LTV:CAC ratio and the CAC payback period rather than as a target in itself.

How to use this calculator.

  1. Pick a period and hold it fixed. A quarter is the usual choice for a company with a sales team; a month works for self-serve products. Every figure you enter must describe the same window.
  2. Choose the basis. Blended answers 'what did growth cost us on average?'. Paid answers 'what does it cost to buy one more customer?'. If you are preparing an investor update, compute both.
  3. Enter paid-channel acquisition spend: media and ad spend, agency and affiliate fees, referral bounties, acquisition discounts and credits, and the loaded cost of salespeople who work only paid leads.
  4. Enter other acquisition cost: brand and content marketing, PR, events, marketing tools, and inbound sales headcount. Decide once whether you follow Bessemer and include the sales-linked share of customer success, then keep that decision every period and disclose it.
  5. Enter new customers, split by paid and organic attribution. Count paying customers only — not signups, trials, leads or ad-platform conversions. If you cannot separate organic, leave it at zero and read the paid figure.
  6. Read the numerator and denominator tiles to confirm the calculator divided what you meant it to divide, then take the CAC into the LTV:CAC ratio and CAC payback calculators, where it turns into a decision.

The formula.

CAC = (S_paid + S_other) ⁄ (N_paid + N_organic) · CAC_paid = S_paid ⁄ N_paid
S_paid · paid-channel acquisition spend for the periodS_other · acquisition cost with no paid attributionN_paid · new customers attributed to paid channelsN_organic · new customers with no paid attribution

Blended CAC adds the two spend fields and divides by the two customer counts added together. Paid CAC divides the paid spend field by the paid customer count alone, ignoring both non-paid cost and organically acquired customers. The supporting outputs are simple: total acquisition spend is the sum of the two cost fields, total new customers is the sum of the two counts, and the organic share is organic customers divided by total customers times 100. Rounding happens at one place only. Every sum and every quotient is carried at full arbitrary-precision decimal, and the result is rounded once, at the moment it is returned, to ten decimal places — the currency and percentage displays then show two. There is no intermediate rounding, and there are no thresholds or bands in this formula, so no result can be nudged across a boundary by an earlier rounding step. Two domain rules are enforced. Spend of zero is legal, because a quarter won entirely by word of mouth genuinely has a CAC of $0. A denominator of zero is not legal: with no new customers the metric is undefined, and the calculator raises a field error rather than returning infinity. Selecting the paid basis with zero paid customers raises the same kind of error, with a message telling you to switch to blended.

A worked example.

Example

A small B2B SaaS company closes its quarter. It spent $40,000 on paid channels — search ads, a review-site listing, and an affiliate programme — and another $20,000 on things it cannot attribute to a channel: a content writer, a conference booth, and marketing tooling. Four hundred customers started paying: 250 tagged to a paid source, 150 arriving direct or by referral. On the blended basis the calculator divides $60,000 of total acquisition spend by 400 total new customers and returns a CAC of $150.00. Switch the basis to paid and it divides $40,000 by 250, returning $160.00. The organic share tile reads 37.5%, which is the reason the two numbers differ at all. Note the direction: blended is the lower of the two here, because those 150 free customers cut the denominator by 60% while the extra $20,000 lifted the numerator by only 50%. That relationship is not fixed. If the same $20,000 of brand spend had produced only 20 organic customers instead of 150, blended CAC would be $60,000 ÷ 270 = $222.22 — well above the $160 paid figure — and the company would be discovering that its unattributed marketing is the expensive half of the mix. This is the reason to compute both and to publish the numerator and denominator alongside: the headline number on its own does not tell you which of those two stories you are in. As a next step the company would take the $160 paid CAC into the CAC payback calculator with its monthly gross profit per customer, and into the LTV:CAC ratio against its lifetime value, which is where a CAC figure stops being trivia and starts being a budget decision.

other Acquisition Cost20,000
paid Channel Spend40,000
customers From Organic150
customers From Paid250
cost Basisblended

Frequently asked questions.

What is the formula for customer acquisition cost?
CAC equals total acquisition spend for a period divided by the number of new customers acquired in that period. On the blended basis that is all acquisition cost over all new customers; on the paid basis it is paid-channel spend over the customers paid channels produced. In the worked example, $60,000 over 400 customers gives a blended CAC of $150.00, while $40,000 over 250 paid-attributed customers gives a paid CAC of $160.00. The arithmetic is trivial; almost all of the difficulty in CAC is deciding what belongs in the numerator and what counts as a customer in the denominator.
What costs should be included in CAC?
There is no single answer, which is itself the most important fact about the metric. David Skok's definition uses the sales and marketing expense line. a16z requires "the full cost of acquiring users" and explicitly names referral fees, credits and discounts — items that usually sit in contra-revenue rather than in S&M, so a16z's CAC is broader than Skok's. Bessemer's Scaling to $100 Million describes sales and marketing as including sales compensation, content and brand marketing, demand generation, and the customer-success expense that relates to sales, which is broader again. Pick one scope, write it down, apply it every period, and disclose it whenever you publish the number. Changing scope silently between quarters is the failure mode SEC Release 33-10751 was written to address.
What is the difference between blended CAC and paid CAC?
Blended CAC divides all acquisition spend by all new customers, including those acquired organically at no marginal cost. Paid CAC divides paid-channel spend by the customers paid channels produced. a16z's illustration: if half your users cost $100 each through paid marketing and the other half arrive free, paid CAC is $100 and blended CAC is $50. Investors generally weight paid CAC because it tells you whether you can scale spend profitably, while blended tells you what growth cost on average. Blended is not automatically the smaller figure — in the worked example on this page blended is $150 and paid is $160, because organic volume dilutes the denominator faster than unattributed spend inflates the numerator.
Is CAC the same as CPA or cost per acquisition?
No, and treating them as interchangeable is one of the most common reporting errors. CPA is an ad-platform metric: campaign spend divided by the number of conversion events you configured, which is usually a lead, a trial start or an add-to-cart, and is measured inside a single ad account. CAC is a company-level metric: all acquisition spend over all new paying customers, across every channel, for a period. Because a CPA conversion is normally an earlier step in the funnel than a paying customer, CPA is typically far lower than CAC — a $40 CPA and a $160 CAC can describe the same campaign at a 25% trial-to-paid conversion rate. Never put the two in the same table without labelling which is which.
What is a good CAC?
CAC has no meaningful benchmark on its own, because it scales with the price and contract length of what you sell. A $2,000 CAC is unremarkable for enterprise software with a $40,000 annual contract and ruinous for a $9-a-month consumer subscription. The two benchmarks that do exist are ratios. Bessemer recommends investing in customer acquisition when CLTV to CAC is 3x or better, and notes that below 1x you are losing money on every additional customer. On payback, Bessemer's segment targets are under 12 months for SMB-focused businesses, under 18 months for mid-market, and under 24 months for enterprise, with the average CAC payback in their $1–10M ARR bucket sitting at 15 months. Judge your CAC through those ratios, not against another company's dollar figure.
Does CAC include the salaries of the sales team?
Under every mainstream definition, yes — fully loaded compensation, including commissions, for the people whose job is winning new customers. What varies is the treatment of staff who do both new business and renewals. Bessemer's sales and marketing definition explicitly folds in the customer-success expense that relates to sales, meaning the renewal, upsell and cross-sell portion, on the reasoning that those costs are part of the go-to-market engine. A narrower reading keeps pure account management out of CAC on the reasoning that retention spend is not acquisition spend. Both are defensible. Split the person's cost by time if you can measure it, apply the same split every period, and state which convention you used.
Why does my CAC not match my income statement?
Because CAC and GAAP answer different questions. FASB ASC 340-40 requires an entity to recognise as an asset the incremental costs of obtaining a contract — a sales commission being the canonical example — when it expects to recover them, and then to amortise that asset as the goods or services are transferred. CAC expenses the whole cost in the period the customer was won. So a company with growing bookings will show a smaller commission expense on its income statement than its CAC calculation charges, because part of the commission has been capitalised onto the balance sheet. Neither figure is wrong. If you reconcile them, do it explicitly rather than adjusting one to match the other.
How often should CAC be recalculated?
Every period you report on, and always on the same period length. Monthly works for self-serve products where the sales cycle is days; quarterly is more honest for anything with a sales cycle longer than a month, because monthly CAC in a sales-led business attributes this month's spend to customers who were actually worked for two quarters. If your sales cycle exceeds your reporting period, consider lagging the numerator — Bessemer measures CAC payback using the prior period's sales and marketing expense against the current period's new revenue for exactly this reason. Whatever you choose, keep it stable: a change in period or in lag will move CAC more than most real operational improvements do.
Should I focus on lowering CAC or improving retention?
Retention, in almost every case, and there is a primary source for that. Gupta, Lehmann and Stuart's 2004 Journal of Marketing Research paper valued the customer bases of Capital One, Amazon, eBay, Ameritrade and E*Trade and reported the elasticity of customer value to each lever: a 1% improvement in retention raised customer value by 2.45% to 6.75% across the five firms, a 1% improvement in margin by roughly 1%, and a 1% improvement in acquisition cost by only 0.02% to 0.3%. Cutting CAC by a tenth is difficult and moves firm value by a rounding error; cutting churn by a tenth is difficult and moves it substantially. Compute CAC because you need it for the ratios — but spend your effort further down the funnel.

References& sources.

  1. [1]Andreessen Horowitz — Jordan, J., Hariharan, A., Chen, F., & Kasireddy, P. (21 August 2015). "16 Startup Metrics." Metric 7 defines CAC as "the full cost of acquiring users, stated on a per user basis" and gives the blended vs paid distinction and the $100/$50 illustration used on this page. Open web, retrieved 2026-07-29.
  2. [2]Skok, D. "SaaS Metrics 2.0 — Detailed Definitions," forEntrepreneurs.com. Gives CAC as "Sales & Marketing Expenses / Number of New Customers Acquired" and notes the distortion in early-stage companies. Undated revision, current as retrieved 2026-07-29.
  3. [3]Bessemer Venture Partners — D'Onofrio, M. "Scaling to $100 Million" (updated 2024 edition, PDF). Source of the wider S&M scope quoted on this page ("sales expenses, sales compensation, content and brand marketing, demand generation, and customer success expenses related to sales") and of the 3x CLTV/CAC and segment payback benchmarks. Open web PDF, retrieved 2026-07-29.
  4. [4]U.S. Securities and Exchange Commission — "Commission Guidance on Management's Discussion and Analysis of Financial Condition and Results of Operations," Release Nos. 33-10751; 34-88094; FR-87, issued 30 January 2020, effective 25 February 2020. Section on Key Performance Indicators and Metrics requires "a clear definition of the metric and how it is calculated," a statement of why it is useful and how management uses it, and disclosure of any change in the method of calculation. Federal Register text via GovInfo (sec.gov blocks automated retrieval); retrieved 2026-07-29.
  5. [5]Gupta, S., Lehmann, D. R., & Stuart, J. A. (2004). "Valuing Customers." Journal of Marketing Research, 41(1), 7–18. Cohort model equations (3) and (6) subtract acquisition cost c_k per customer at acquisition; Table 4 reports acquisition-cost elasticity of 0.02–0.3 against retention elasticity of 2.45–6.75. Author copy hosted by Columbia Business School; retrieved 2026-07-29.
  6. [6]Financial Accounting Standards Board — Accounting Standards Codification Topic 340-40, "Other Assets and Deferred Costs — Contracts with Customers," paragraphs 340-40-25-1 to 25-4 (added by ASU 2014-09, Revenue from Contracts with Customers (Topic 606)). Requires incremental costs of obtaining a contract, such as a sales commission, to be recognised as an asset when recovery is expected. Bibliographic citation only: the Codification is behind a free-registration wall, so no verbatim text is attributed to the link.
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