A Micro-SaaS Financial Model You Can Build Tonight

You don't need a CFO-grade model for a micro-SaaS. You need five numbers that interact correctly, so you can see when (or if) the project pays your rent. Here is the whole model — build it in any spreadsheet in under an hour.

The five inputs

1. Price (P). Pick two tiers, e.g. $19 and $49/month. Use blended price: if you expect 70/30 mix, P = 0.7×19 + 0.3×49 ≈ $28.
2. New customers per month (N). Be brutal here. From cold email at 1–3% reply-to-customer conversion, or content after 6 months of compounding. Most first-year micro-SaaS products add 5–20 customers/month, not 100.
3. Monthly churn (c). For self-serve SMB tools: 4–7% is normal, not 1%. If your model only works at 2% churn, it doesn't work.
4. Variable costs (V). Payment processing ~3%, hosting per customer, API costs. Usually $1–4/customer/month plus a fixed base.
5. Fixed costs (F). Hosting baseline, domains, software, accounting. Often $100–300/month pre-salary.

The monthly engine (copy these formulas)

• Customers[m] = Customers[m−1] × (1 − c) + N
• MRR[m] = Customers[m] × P
• Gross profit[m] = MRR[m] × (1 − V%)
• Net[m] = Gross profit[m] − F − (your salary line, if you pay yourself)

Run it for 24 months. Two things will jump out immediately:

• Steady state ceiling: customers converge toward N ÷ c. At N=15 and c=5%, you plateau near 300 customers (~$8,400 MRR at P=$28). That's your ceiling unless you raise N or cut c — better to know on day one.
• Break-even month: where Net turns positive. With those numbers it lands around month 14–16 without salary. Every "we'll grow faster" fantasy should be tested against this row.

Three sanity checks

• LTV/CAC: LTV = P × gross margin ÷ c. At P=$28, margin 85%, c=5% → LTV ≈ $476. If acquiring a customer costs more than a quarter of that through paid channels, paid doesn't work yet — go organic.
• The annual-plan trap: modeling everything as monthly overstates cash early. Add a column assuming 20% pick annual plans and see what happens to months 1–6.
• Refund/dunning haircut: subtract 3–5% from every revenue line. Involuntary churn is real.

Don't build it from scratch

This model — with the formulas, the ceiling calculation, and a 36-month version — is exactly what the Prévio packs ($29/$49) ship as a ready spreadsheet, alongside a pre-filled business plan document.

Or start free: 1-page business plan template →