About this calculator

How-to: enter cash in bank, monthly operating expenses, current MRR, gross margin % and monthly MRR growth rate. Gross burn = OpEx. Net burn = OpEx − MRR × GM%. Runway = cash ÷ net burn. Default-alive (Paul Graham) is true when, holding growth constant, the company reaches profitability before cash runs out.

Frequently asked questions

Should I use gross or net burn?

Both. Net burn drives runway; gross burn drives OpEx discipline. If gross ≫ net, you're growing fast; if net ≈ gross, you have little revenue cushion.

What is 'default-alive'?

Paul Graham's test: at current growth and cost trajectory, would you become profitable before running out of cash? If yes, you're default-alive and don't need to raise.

Which gross margin should I plug in?

SaaS COGS: hosting, third-party APIs, customer success salaries, payment processing. Exclude R&D and sales. Healthy vertical SaaS is 70–85%, infra SaaS 55–75%.

What does the SaaS Burn Rate & Runway Calculator do?

Monthly gross and net burn, months of runway, default-alive check, and the ARR growth rate needed to hit default-alive before cash runs out — the metrics every SaaS board reviews. How-to: enter cash in bank, monthly operating expenses, current MRR, gross margin % and monthly MRR growth rate. Gross burn = OpEx. Net burn = OpEx − MRR × GM%. Runway = cash ÷ net burn. Default-alive (Paul Graham) is true when, holding growth constant, the company reaches profitability before cash runs out.

Is the SaaS Burn Rate & Runway Calculator free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the SaaS Burn Rate & Runway Calculator?

Results are calculated in real time using industry-standard formulas. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified saas & startups professional before committing to a purchase or a job.

What inputs does the SaaS Burn Rate & Runway Calculator need?

Enter values for: Cash in bank, Currency, Monthly OpEx (fully loaded), Current MRR, Gross margin (%), Monthly MRR growth (%). Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the SaaS Burn Rate & Runway Calculator on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.