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★ What does it cost to win one new customer?

Customer Acquisition Cost (CAC) Calculator

Calculate customer acquisition cost from sales and marketing spend and new customers. Free CAC calculator with blended vs paid CAC explained.

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$

Ads, tools, salaries and commissions for the period.

accts

Won in the same period.

Your CAC

$500

CAC = sales & marketing spend ÷ new customers acquired (same period)

CAC: $500.

Paid CAC too high? Free tools like this one are how I'd lower it. Want one for your product?

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01

How it works

CAC = sales & marketing spend ÷ new customers acquired (same period)

Add up everything you spent to acquire customers in a period: ad spend, sales and marketing salaries, commissions, tools and agencies. Divide by the number of new customers you won in the same period.

Blended CAC counts every new customer, including ones who found you organically. Paid CAC only counts customers from paid channels against paid spend. Report both: blended flatters you, paid tells you whether ads work.

02

Worked example

A startup spends $30,000 in a month on ads, a part-time marketer and sales tools, and signs 60 new customers.

CAC worked example
InputValue
Sales & marketing spend$30,000
New customers60
CAC$500
03

Benchmarks

CAC has no universal benchmark: a $50 CAC can be terrible for a $5/month app and great for a $500/month tool. Judge it through the LTV:CAC ratio and the CAC payback period.

Directional: these are rules of thumb, not universal standards. Compare yourself with companies at your stage, selling to the same kind of customer.

Source: David Skok, SaaS Metrics 2.0 (Matrix Partners).

04

How to improve it

  • Invest in channels that compound: SEO content, free tools, integrations and referrals.
  • Fix conversion before buying more traffic. Doubling trial-to-paid conversion halves CAC.
  • Cut channels whose paid CAC exceeds what the customer pays back in the first year.
  • Shorten the sales cycle with self-serve onboarding for smaller accounts.
05

Questions founders actually ask

Should salaries be included in CAC?
Yes, for a fully loaded CAC. Include the share of sales and marketing salaries spent on acquisition. Leaving them out makes CAC look far better than it is.
What's the difference between blended and paid CAC?
Blended CAC divides all acquisition spend by all new customers, including organic ones. Paid CAC only counts customers from paid channels. Blended is the headline number; paid tells you whether advertising pays off.
What time period should I use?
Match the period to your sales cycle. For self-serve products a month works. For sales-led products with a 90-day cycle, use spend from the previous quarter against customers won this quarter.
Is a low CAC always good?
Not necessarily. A very low CAC with high churn can still lose money, and a low CAC sometimes means you are under-investing in growth. Look at it alongside LTV and payback.
06

Related metrics

07

More from the workbench

Fine print

Tools: on the house.
Engineer: by the hour.

Moving them is the expensive part, and the part I'm good at: activation flows, upsell moments and the product work behind better numbers.

I'm Himanshu, an AI and full-stack engineer. I build MVPs, AI agents and the growth plumbing around them for early-stage startups.