Know your runway, burn multiple, and Rule of 40 score. Built for Series A/B founders who need clarity before their next board meeting.
Calculate Your RunwayEnter your current monthly numbers. We'll calculate everything from here.
Break down your expenses for a detailed composition chart. These should sum to your total opex above.
Unlock scenario modeling, fundraising timing, and benchmarks vs. industry medians.
Burn rate is the single most critical metric for venture-backed SaaS companies. It tells you how fast you're spending cash — and combined with your MRR growth trajectory, determines exactly when you'll need to raise your next round or achieve profitability.
Gross burn rate is your total monthly operating expenditure — everything from engineering salaries to AWS bills. Net burn rate subtracts your revenue, showing the actual cash you're consuming each month. For a SaaS company doing $150K MRR with $250K in monthly expenses, the gross burn is $250K and the net burn is $100K.
The burn multiple (coined by David Sacks) measures how much you're spending to generate each dollar of net new ARR. A burn multiple under 1x is exceptional — you're adding ARR faster than you're burning cash. Between 1–2x is good for growth-stage SaaS. Above 3x means your unit economics likely need work. VCs increasingly use burn multiple as a key efficiency metric during due diligence.
The Rule of 40 states that a healthy SaaS company's combined growth rate and profit margin should exceed 40%. If you're growing MRR at 10% month-over-month (roughly 214% annualized) with a –30% profit margin, your Rule of 40 score is 184 — well above the benchmark. This metric helps balance growth vs. profitability.
Most VCs recommend starting your fundraise when you have 9–12 months of runway remaining. The average Series B raise takes 3–6 months from first meeting to wire. Waiting until you have less than 6 months of cash puts you in a weak negotiating position and can lead to down rounds or unfavorable terms.
For more on the financial metrics every SaaS founder should track, read our guide on SaaS Financial Metrics for Series A Companies.