SaaS MVP Runway & Unit Economics Calculator

Free financial modeling utility for startup founders: Calculate cash runway months, net burn rate, LTV-to-CAC ratios, and CAC payback periods with dynamic revenue growth.

1. Cash Reserves & Monthly Cashflow

Total Bank Balance ($)

Monthly Expenses (Gross Burn) ($)

Monthly Recurring Revenue (MRR) ($)

Monthly Revenue Growth (%)

2. Unit Economics (LTV & CAC)

Avg. Revenue Per User (ARPU) ($/mo)

Customer Acquisition Cost (CAC) ($)

Monthly Customer Churn Rate (%)

Estimated Startup Runway

14.2 Months

✅ Healthy Runway (> 12 Months)

Net Monthly Burn

-$11,500/mo

Customer Lifetime Value (LTV)

$1,755

LTV to CAC Ratio

6.3 : 1 (Excellent)

CAC Payback Period

3.5 Months

The Essential Guide to Startup Runway & SaaS Unit Economics

Managing cashflow is the single most critical survival discipline for early-stage software companies and indie hackers. Without visibility into your net burn and customer acquisition efficiency, even revenue-generating startups can unexpectedly hit zero cash.

Gross Burn vs. Net Burn

Gross Burn represents the total amount of cash leaving your bank account each month (salaries, server hosting, software subscriptions, office space). Net Burn subtracts incoming revenue: Net Burn = Gross Expenses − Monthly Recurring Revenue (MRR). Your true runway is your current liquid cash divided by your net burn.

The 3:1 LTV:CAC Benchmark

In modern SaaS benchmarks, a Customer Lifetime Value to Customer Acquisition Cost ratio of 3:1 is considered the gold standard of healthy unit economics:

Under 1:1: Unsustainable. You lose money on every acquired customer.
1:1 to 2.5:1: Marginally viable, but leaves little margin for operational overhead or churn spikes.
3:1 to 5:1: Healthy, profitable growth engine ready for marketing scale.
Over 6:1: Extremely efficient; you are likely under-investing in marketing and could grow faster.