Burn Rate Calculator
Calculate your monthly cash burn and see exactly how many months of runway you have left with a visual cash balance chart.
Runway
14.3months
Cash runs out approximately October 2027
Gross Burn Rate
$45,000/mo
Net Burn Rate
$35,000/mo
Starting Capital
$500,000
Cash Runway
How to Use the Burn Rate Calculator
1. Enter Your Starting Cash / Runway Capital. Use your current cash balance across all business accounts — the actual amount available to spend, not revenue you're expecting or a credit line you haven't drawn on. This is the number the entire runway calculation counts down from.
2. Enter Your Monthly Operating Expenses. Include every recurring cost your business pays out each month — payroll, rent, software subscriptions, contractor fees, and any other regular spend. This becomes your Gross Burn Rate, the full picture of cash leaving the business before any revenue is factored in.
3. Enter Your Monthly Revenue (optional). Add whatever revenue you're currently generating, if any. This is subtracted from your gross burn to calculate Net Burn Rate — the number that actually determines how fast your cash balance is shrinking, and the figure most investors care about most.
4. Read Your Results. The calculator shows your Runway in months along with an estimated calendar date your cash reaches zero, your Gross Burn Rate, and your Net Burn Rate. The month-by-month chart plots your projected cash balance declining over time, with a dashed line marking the point it hits zero. If your revenue already covers your expenses, the calculator switches to a "Profitable — No Burn" state and shows your monthly surplus instead of a countdown.
Kwame ran his SaaS startup's numbers through the calculator: $500,000 in cash, $45,000 in monthly operating expenses, and $10,000 in monthly revenue. The result came back as a 14.3-month runway, with cash projected to run out around October 2027 — more than a year of breathing room, which felt comfortable. What he hadn't factored into that number was a hiring plan already in motion: two engineers starting in month three, adding $12,000 a month in combined salary and overhead. Recalculating month by month, his burn stayed at the same $35,000 net for the first two months, but jumped to $47,000 net from month three onward once the new hires started. Working through the math, his actual runway came out closer to 11 months instead of 14.3 — a three-month gap that the calculator's single snapshot number couldn't have shown him, because it assumed his current burn rate would hold steady indefinitely. He used the shorter, more realistic number to start fundraising conversations several months earlier than he'd originally planned.
Key Terms
Starting Cash / Runway Capital
Your current, actual cash balance across all business bank accounts — the total amount of capital available to fund operations going forward.
Gross Burn Rate
Your total monthly operating expenses, regardless of any revenue coming in — every dollar leaving the business each month.
Net Burn Rate
Gross burn rate minus monthly revenue — the true rate at which your cash balance is declining. This is the number that determines your actual runway.
Cash Runway
Starting cash divided by net burn rate, expressed in months — the length of time your business can keep operating at its current spending and revenue levels before running out of cash.
"Profitable — No Burn" State
What the calculator shows when monthly revenue meets or exceeds monthly expenses, replacing the runway countdown with a monthly surplus figure instead. Reaching this state removes the cash-out clock entirely.
Why Your Runway Number Assumes Nothing About Your Business Will Change
The runway figure this calculator gives you is accurate for exactly one thing: what happens if your spending and revenue stay exactly where they are today, every single month, until the cash runs out. For most growing businesses, that assumption rarely holds for long — and treating a single snapshot as a fixed deadline is one of the most common ways founders get caught off guard by their own cash position.
Expenses Tend to Step Up, Not Stay Flat
A planned hire, a bigger office lease, an increase in ad spend, or an annual software contract renewal can all raise your burn rate substantially the moment they hit, even if your current monthly numbers look stable today. A $500,000 balance burning at $35,000 a month gives you over 14 months on paper — but if you're planning to add $12,000 a month in new hires three months from now, your real runway is meaningfully shorter than the number the calculator shows using today's burn rate alone.
The Fix Is Running the Numbers More Than Once
Rather than relying on a single calculation, run this calculator with your current burn rate first, then run it again using your burn rate after any planned hires, contract renewals, or spending increases you already know are coming. The gap between those two numbers is exactly how much cushion your "official" runway figure is quietly missing.
Treat Runway as a Living Number, Not a One-Time Answer
Startups that revisit this calculation monthly, updating it with actual spending and any newly confirmed future costs, catch a shrinking runway months before it becomes a crisis. If your actual burn consistently runs ahead of what you calculated, that drift compounds — a few thousand dollars of unaccounted spending each month can shave a meaningful chunk off a runway that once looked comfortable.