I built a free CAC Payback & Unit Economics benchmark calculator for SaaS founders (No signup required)

Hey Indie Hackers 👋

A common issue I noticed when founders calculate their customer acquisition cost (CAC) payback is relying on naive math:

The problem? If you acquire a customer for

500/mo ARPA, basic math says you break even in12 months.

But when you factor in real-world economics—75% Gross Margin (hosting, payment fees, support) and 2.5% monthly churn drag—the true breakeven is 18.4 months. That 6-month blind spot can quietly burn through a startup’s runway.

To solve this, I built BestSaaSMetrics (https://bestsaasmetrics.com) — a fast, free, and visual SaaS unit economics modeler.

🛠️ What it does:

1. True Gross-Margin & Churn-Adjusted Payback: Calculates your exact breakeven month accounting for COGS, churn rate decay, and sales cycle latency.

2. 36-Month Cumulative Cash Flow Trajectory: Visualizes the exact month your customer cohort turns cash-flow positive.

3. 8 Vertical Benchmark Presets: Compare your numbers instantly against:

   • Bootstrapped & Micro-SaaS

   • Product-Led Growth (PLG)

   • Enterprise B2B SaaS

   • Developer Tools & API Infra

   • FinTech & Payments

   • HealthTech, EdTech, and SalesTech / CRM

4. Side-by-Side Scenario Modeling: Test how a 10% ARPA increase compares against a 1% churn reduction on your payback speed.

💡 Why I built it this way:

• Zero friction: No email capture, no account creation, no paywall.

• Client-side instant calculations: React + dynamic visualization charts for instant feedback.

• Focused purely on utility: Designed to give founders and finance leads immediate answers in under 60 seconds.

🔗 Try it out:

Check it out at: https://bestsaasmetrics.com

I'd love feedback from fellow founders:

1. What CAC payback window is your business currently targeting?

2. Are there other SaaS metrics (e.g. Magic Number, Rule of 40, Net Revenue Retention) you'd like to see added next?