# Calculate CAC payback, magic number, and burn multiple for my SaaS

Your core SaaS efficiency metrics calculated correctly, benchmarked by stage, and turned into a short diagnosis.

- Topic: Finance & Accounting
- Framework: RTF
- Level: Advanced
- Tags: Finance, Fill-in Template
- Source: https://www.thinkwithprompt.com/prompts/calculate-cac-payback-magic-number-and-burn-multiple-for-my-saas

## Prompt

```text
Calculate the go-to-market efficiency metrics for my SaaS business.

**Period data (quarterly preferred):** [new ARR, expansion ARR, churned and contracted ARR, sales and marketing spend, gross margin %, net burn, starting and ending ARR]
**Number of new customers and average ARR per new customer:** [DATA]
**Business model:** [self-serve / sales-led / hybrid] **Stage:** [e.g. seed, Series A, $5M ARR]
**How we account for S&M:** [what is included - salaries, commissions, tools, agencies]

Calculate, showing the formula and inputs for each:
1. CAC (blended, and paid if I give channel data).
2. CAC payback in months = period S&M spend / (new ARR added in the period x gross margin %) x 12, using prior-period spend if I specify a lag. Keep units consistent (ARR is annual) and state them.
3. Magic number = (this quarter's revenue minus last quarter's revenue) x 4 / prior-quarter S&M spend (net new ARR / prior-quarter S&M as an approximation).
4. Burn multiple = net burn / net new ARR.
5. Net revenue retention and gross revenue retention, if data allows.
6. LTV:CAC, only with a stated churn assumption, and a note on why it can mislead at early stage.

Then:
- Compare each metric to commonly cited ranges for my stage and model, labeled as rough rules of thumb, not standards.
- Diagnose the biggest drag (low win rates, high churn, low margin, overspend) and what data would confirm it.
- List 3 actions ranked by likely impact.
- Flag any inconsistent or missing inputs instead of guessing.

Output: a metrics table, a 150-word diagnosis, and the action list.
```

## What to fill in

- DATA
- self-serve / sales-led / hybrid
- e.g. seed, Series A, $5M ARR
- what is included - salaries, commissions, tools, agencies

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