# Startup runway calculator: burn rate and months of cash A startup runway calculator works out how many months of cash you have left. Net burn is monthly expenses minus revenue, and runway is the month cash would reach zero, forecast one month at a time with your growth rates. You get your runway, the runway if nothing changes, and the burn you can afford to reach the runway you want. Use it free, with no signup, at https://getlaunchlist.com/tools/startup-runway-calculator. Updated 2026-10-15. ## What you enter - **Cash in the bank**: The cash you have today. - **Monthly expenses (gross burn)**: Everything you spend in a month: pay, tools, hosting, ads. - **Monthly revenue**: What you collect in a month. - **Monthly revenue growth**: Your own assumption, compounding each month. Set it to 0% to see the floor. - **Monthly expense growth**: Hires and tools you plan to add. A cut is a negative number. - **Runway you want**: Your target in months, used to work out the burn you can afford. ## How it's calculated Runway is the number of months until cash reaches zero. The calculator forecasts your cash one month at a time. - **Gross burn** is your monthly expenses. **Net burn = expenses - revenue.** - **Revenue in month m = revenue × (1 + revenue growth)^(m - 1).** Expenses grow the same way at the expense growth you enter. - **Cash after month m = cash before - expenses + revenue.** - **Runway** is the month cash would go below zero, with the part of that month your remaining cash covers counted as a fraction: **remaining cash ÷ (expenses - revenue)** in that month. - **Runway with no change = cash ÷ net burn**, with revenue and expenses held at today's level. - **Net burn for your target = cash ÷ months you want.** The cut is today's net burn minus that. ## How to read the result The headline is the date cash runs out if your growth assumptions hold. The runway with no change is the figure that needs no assumption, so compare the two: the gap is how much of your runway depends on growth you have not yet earned. If revenue covers expenses within the forecast, the lowest cash balance shows whether you get there before the money does. A negative lowest balance is the cash you would need to add. ## What moves it Net burn is the biggest lever, and it moves from both sides: each dollar of expenses cut and each dollar of revenue added count the same. Growth compounds, so a small change to the growth rate matters more the further out you look, which is also why you should enter a rate you have actually seen. The forecast stops at 60 months and does not model one-off costs, taxes or new funding. Add a raise by adding it to your cash. ## Frequently asked questions ### What is startup runway? Runway is how many months you can keep operating before cash reaches zero. The simple version is cash on hand divided by net monthly burn, where net burn is monthly expenses minus monthly revenue. ### What is the difference between gross burn and net burn? Gross burn is everything you spend in a month. Net burn is what you spend after revenue is subtracted, so it is the number your cash balance actually falls by. Runway uses net burn. ### How do I calculate my burn rate? Add up what left your accounts in a recent month and subtract what came in as revenue. Averaging the last three months smooths out one-off payments. That figure is your net burn rate. ### How do I extend my runway? Four moves change it: spend less, earn more, raise cash, or do less before you know people want it. Try each in the calculator: lower the expenses, raise the revenue, add a raise to your cash, and watch the months change. The burn for your target figure tells you how large a cut you need. ### Should I count growth in my runway? Only growth you have seen. Compare the headline runway with the runway with no change. The difference is the part that depends on growth you have not earned yet, so plan around the lower number until the revenue arrives. ### How can a waitlist help when cash is tight? A waitlist is a cheap way to find out whether people want the product before you spend runway building it. It costs a page and a few weeks of effort rather than months of salary, and the signups you collect are evidence you can show to customers or investors. ## Related tools - [Pre-launch MRR calculator](https://getlaunchlist.com/tools/prelaunch-mrr-projector.md): Project launch-day MRR and the first year of revenue from your waitlist, price and churn. - [Startup idea validator](https://getlaunchlist.com/tools/idea-validation-scorecard.md): Score the evidence behind your startup idea and choose your next validation step. - [Product Hunt upvote calculator](https://getlaunchlist.com/tools/launch-day-forecaster.md): Estimate the upvotes your own list and network bring to a Product Hunt launch, and what closes the gap. - [Waitlist growth simulator](https://getlaunchlist.com/tools/waitlist-growth-simulator.md): Project how big your waitlist gets in the weeks before launch, with and without referrals.