The Real Cost of a Customer: Calculating CAC and LTV Correctly
CAC and LTV calculations are often wrong. Learn the real formulas that include salaries, tools, and all costs—not just ad spend.
You're calculating CAC wrong. It's not just ad spend divided by customers. Here's the real formula that includes all costs.
The Simple Formula vs. The Real Formula
Most people use the simple formula. It's wrong:
Simple Formula (Wrong)
CAC = Ad Spend / Customers Acquired
Example: $10,000 / 100 customers = $100 CAC
Problem: Ignores salaries, tools, overhead, and other costs
Real Formula (Correct)
CAC = (Ad Spend + Salaries + Tools + Overhead) / Customers Acquired
Example: ($10,000 + $20,000 + $2,000 + $3,000) / 100 = $350 CAC
Reality: Your real CAC is 3.5x higher than you thought
Including Salaries and Tools in CAC
Here's what to include:
What Counts as Marketing Cost
- Ad spend: Google Ads, Facebook, LinkedIn, etc.
- Salaries: Marketing team salaries (prorated)
- Tools: CRM, email platform, analytics, etc.
- Content: Design, copywriting, video production
- Overhead: Office space, utilities (marketing %)
- Agency fees: If using agencies
How to Calculate
- Add all marketing costs for the period (month/quarter)
- Divide by customers acquired in that period
- That's your real CAC
Calculating Lifetime Value (LTV)
LTV is how much a customer is worth:
The Formula
LTV = Average Revenue Per Customer × Gross Margin % × Average Customer Lifespan
Example: $1,000 × 70% × 3 years = $2,100 LTV
What to Include
- Initial purchase: First sale value
- Upsells: Additional products/services
- Renewals: Subscription renewals
- Expansion: Account growth
- Referrals: Value of referrals they bring
The Golden Ratio: LTV:CAC of 3:1
The target ratio:
Why 3:1?
- 1:1 = Break even (not sustainable)
- 2:1 = Profitable but tight
- 3:1 = Healthy (room for growth and profit)
- 4:1+ = Excellent (can scale aggressively)
What If You're Below 3:1?
- Lower CAC (improve conversion, optimize ads)
- Increase LTV (upsells, retention, expansion)
- Or both
How to Lower CAC by Improving Conversion
Better conversion = Lower CAC:
The Math
- Current: $100 CPL, 10% conversion = $1,000 CAC
- Improve conversion to 20% = $500 CAC
- Same ad spend, double the customers
How to Improve Conversion
- Better landing pages
- Faster response time
- Better lead quality
- Improved sales process
Conclusion
Calculate CAC correctly by including all costs (salaries, tools, overhead), not just ad spend. Calculate LTV including all revenue streams. Target a 3:1 LTV:CAC ratio. Lower CAC by improving conversion rates. The result? Accurate metrics and better business decisions.
