Customer Acquisition Cost (CAC) calculator

CAC — the cost of growth, fully loaded

Customer acquisition cost is the total money you spend to get one new customer, divided by the number of new customers in that period. The math is simple; the discipline is in including all the right costs. Most CAC numbers founders quote are understated by 30–50% because they exclude sales salaries, ops overhead, or free trial costs.

The fully-loaded CAC formula

CAC = (Sales + Marketing + Allocated Overhead) ÷ New Customers

Sales includes: base salaries, commissions, OTE-weighted comp, SDR/BDR team, sales tools (Salesforce, Outreach, ZoomInfo, Gong). Marketing includes: paid ads, content production, SEO tools, marketing automation, events, PR, swag, brand agency. Overhead: allocated portion of CFO/CEO time, office space for those teams, and the fully-loaded CS team that handles onboarding (a grey area — some teams put CS in COGS, some in acquisition).

Blended vs Paid CAC

Blended CAC uses everything in the numerator and all new customers in the denominator — it's your overall cost of growth. Paid CAC isolates just paid marketing / paid sales spend and divides by attributable-to-paid customers. The ratio matters:

• Blended = Paid: You're 100% paid-driven. No word of mouth, no organic — fragile.
• Blended = 0.6–0.8x Paid: Healthy. Organic and referrals are lowering overall cost.
• Blended = 0.3–0.5x Paid: Excellent. Strong brand pulling in customers without direct paid spend.

Calendly, Notion, and Figma famously had blended CAC close to zero for years — paid was real, but product-led growth and virality dwarfed it.

What counts as "new"?

Count net new customers in the period — new logos, not expansions. If a customer churned and came back, treat them as new (winbacks shouldn't dilute CAC). If they expanded from $100/mo to $500/mo, that's expansion revenue, not a new customer — don't count them.

Attribution — the CAC blurrer

Multi-touch attribution is the never-solved problem. If a customer saw a LinkedIn ad, read your blog, got an SDR cold email, attended a webinar, and then signed up — which channel "earned" them? Answer depends on the model:

• First-touch: All credit to the blog (assuming that was their first site visit).
• Last-touch: All credit to the SDR.
• Linear: Equal credit to all 5 touches.
• Position-based (40/20/40): 40% to first, 40% to last, 20% split among middle.
• Time-decay: Weighted toward recent touches.

For early-stage companies, don't overthink it. First-touch attribution plus a self-reported "How did you hear about us?" field at signup gives you 80% of the truth with 5% of the effort.

CAC by channel

Aggregate CAC hides which channels work and which don't. Calculate CAC per channel and prune aggressively:

• Paid search: Typically $100–500 CAC for SMB, $2–10k for enterprise, depending on keywords.
• Paid social: Lower intent than search, so higher CAC but cheaper reach. Good for brand.
• SEO / content: High upfront cost, near-zero marginal cost once ranking. Strongest CAC leverage if you can rank.
• Outbound: SDR cost + commission per booked meeting; high for enterprise.
• Referrals: Near zero — already trusted, high conversion.

CAC payback period

CAC alone doesn't tell you if growth is economic. The key follow-up: CAC Payback Period = CAC / (ARPU × Gross Margin). If you spend $1,000 to acquire a customer who pays $100/mo at 80% gross margin, payback = 1,000 / 80 = 12.5 months. Under 12 months is great; over 24 months is stretched unless retention is exceptional. See the LTV:CAC + payback calculator for the full picture.

Benchmarks by segment

• SMB SaaS (<$500/mo): CAC $50–500, payback 6–12 months
• Mid-market ($500–5k/mo): CAC $2k–15k, payback 12–18 months
• Enterprise ($5k+/mo): CAC $20k–100k+, payback 18–24 months
• E-commerce: CAC 20–30% of AOV typical, 40%+ is loss-leader territory
• Consumer subscription: CAC = 1–3 months of revenue at steady state