Free tool
Compound CAC — what customers actually cost you.
Most CAC calculators stop at paid. Yours doesn't. See how referrals + word-of-mouth drag your effective CAC down over 12 months — and how much of your next year's customer base arrives free.
Paid acquisition
What you spend.
% of customer base lost per month
Compound drivers
What drags your CAC down.
% of active base that refers / mo
Months to hit full referral rate
% from brand / unattributable
Months for brand to kick in
Result
How much your CAC actually shrinks.
- Raw CAC
- ₹5,000
- Month 12 effective CAC
- ₹324
- Free customers (12mo)
- 81.5%
Paid customers only
Dropped 94% vs. raw
5,288 of 6,488 acquired without ad spend
Compound is working. 82% of your 12-month customer haul arrives free via referral + word-of-mouth. Your effective CAC is a fraction of what you actually pay Meta.
Month-by-month
The compound curve.
| Month | Paid | Referral | WOM | Effective CAC | Reduction |
|---|---|---|---|---|---|
| M1 | 100 | 0 | 0 | ₹5,000 | 0% |
| M2 | 100 | 6 | 2 | ₹4,599 | 8% |
| M3 | 100 | 26 | 10 | ₹3,691 | 26% |
| M4 | 100 | 63 | 23 | ₹2,689 | 46% |
| M5 | 100 | 95 | 47 | ₹2,065 | 59% |
| M6 | 100 | 136 | 85 | ₹1,558 | 69% |
| M7 | 100 | 190 | 143 | ₹1,155 | 77% |
| M8 | 100 | 263 | 197 | ₹893 | 82% |
| M9 | 100 | 356 | 267 | ₹691 | 86% |
| M10 | 100 | 476 | 357 | ₹536 | 89% |
| M11 | 100 | 629 | 472 | ₹416 | 92% |
| M12 | 100 | 826 | 619 | ₹324 | 94% |
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