CAC / Payback Period Calculator

How to Use the CAC & Payback Calculator

CAC and Payback Period — The Two Numbers That Decide Whether Your SaaS Scales

10 Facts About SaaS Unit Economics

Frequently Asked Questions

• What's the difference between paid CAC and fully-loaded CAC? +
  Paid CAC includes only paid media spend (Google Ads, Meta, LinkedIn) divided by customers acquired from paid channels. It's useful for setting bid caps and comparing paid channels. Fully-loaded CAC includes ALL sales + marketing costs — paid media, sales team salaries plus commissions, marketing tools, content, events, partnerships — divided by net new customers from ALL channels (paid + organic + referral). When investors ask for "your CAC", they almost always mean fully-loaded. Default to that for board decks; use paid CAC for channel-level optimisation.
• What's a healthy CAC payback period? +
  Bessemer's State of the Cloud places the healthy range at 12-18 months for venture-stage SaaS. SMB SaaS typically achieves 6-12 months because contract sizes are small and conversion is fast. Enterprise SaaS can stretch to 24 months because LTV is much larger and sales cycles longer. Below 12 months is best-in-class; above 24 is risky in any segment. The metric is sensitive to gross margin — a 75% gross margin SaaS has 33% faster payback than a 50% gross margin SaaS at the same CAC and ARPU.
• Should I include free trial users in CAC denominators? +
  No. CAC is computed on paying customers only — net new customers who actually pay. Free trial users who never convert don't contribute to revenue or LTV. Track free-to-paid conversion rate as a separate funnel metric, and use it to derive blended unit economics if needed. The Stripe Atlas SaaS Metrics guide is explicit: CAC denominator is net new paying customers, full stop.
• What's the SaaS Magic Number and how does it relate to CAC? +
  Bessemer's SaaS Magic Number = (Net new ARR this quarter × 4) ÷ S&M spend last quarter. It measures how much new annualised revenue every dollar of S&M produces. Above 1.0 = exceptional growth efficiency; 0.5-1.0 = healthy, keep investing; below 0.5 = slow down acquisition spend until you fix conversion. The Magic Number is conceptually inverted CAC payback — they're two views of the same unit-economics reality. Most SaaS investors report both.
• My LTV:CAC is 8:1 — is that good? +
  8:1 is paradoxically a signal you're under-investing in growth. The Bessemer healthy range is 3:1 to 5:1 — high enough to make money on every customer, low enough that you're spending aggressively to grab market share. Above 5:1, you could likely double S&M spend and still maintain healthy unit economics. The exception: bootstrapped SaaS deliberately running lean — for them, 8:1 reflects intentional discipline rather than under-investment. Venture-backed SaaS targeting growth should push LTV:CAC toward 3:1 by spending more aggressively.
• How do I reduce CAC? +
  Three lever categories: (1) Improve conversion rate at every funnel stage — landing page conversion, trial-to-paid, sales-rep close rate. A 20% conversion lift drops CAC 17%. (2) Shift channel mix from expensive to cheap — paid Google Ads is typically the most expensive channel, organic search and partnerships are typically the cheapest. (3) Raise ARPU on the customers you already win — better pricing tiers, annual prepay incentives, upsell on win-back. ARPU lift doesn't reduce CAC directly but improves LTV:CAC, which is what investors actually watch.
• What time period should I use for CAC? +
  For investor reporting and board decks, use trailing 3 months (TTM is also common — trailing 12 months). For operational dashboards, use rolling 30 days. The trade-off: shorter periods are noisier (one big enterprise deal swings the average), longer periods are more stable but slower to detect changes. A common pattern is to report rolling 30, 60, and 90 day CAC side-by-side so management can see if acquisition is improving or deteriorating recently.
• Should I exclude organic customers from CAC? +
  Two views, both legitimate. The Bessemer convention is fully-loaded: all S&M spend divided by all new customers including organic. This reflects the reality that organic growth still has S&M cost (content marketing, SEO investment, brand spend). The alternative is "paid CAC" — paid media spend only ÷ paid-channel customers. Use paid CAC for channel optimisation (bid caps, ROAS targets) and fully-loaded CAC for investor reporting. They typically differ by 30-60% — paid CAC is usually higher because organic acquisition is "free" in the loaded view.
• How does US SaaS CAC compare to ASEAN markets? +
  US paid CAC is typically 2-4× higher than equivalent ASEAN paid CAC because US click prices on Google Ads / Meta are far higher. But US ARPU is typically 2-3× higher too, so payback periods land in similar 12-18 month ranges across geographies. The big difference is sales-team CAC: US enterprise sales reps cost USD 150-250K fully-loaded; ASEAN equivalents cost USD 50-80K. ASEAN SaaS targeting US markets via remote teams (a common pattern) can get the best of both — US ARPU with ASEAN sales team cost, often producing payback periods under 10 months. See our MRR Calculator for the matching revenue-side math.
• I'm an ASEAN SaaS founder targeting the US — what payback period should I aim for? +
  Under 12 months. Two reasons specific to ASEAN-founded SaaS targeting US: (1) Your remote-team cost structure should produce structurally lower S&M cost than US-headquartered competitors, so a sub-12-month payback proves the cost advantage is real and gives US VCs confidence in your operating leverage; (2) US investors apply higher scrutiny to ASEAN-founded SaaS in the first deal — beating the headline Bessemer benchmark removes one of the standard objections. Once you've raised Series A and demonstrated 12+ months of consistent payback, push CAC by spending more aggressively until payback hits the 12-18 month range.

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