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★ How long do we have?

Startup Runway & Burn Rate Calculator

Cash in the bank, monthly costs, revenue growth. See your runway, the month the money runs out, and whether you're default alive or default dead.

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$
$

Payroll, infra, tools, rent: everything.

$

Recurring revenue this month.

% / mo
% / mo

Runway

60+months

Default aliveRevenue catches expenses before the cash runs out, if these growth rates hold.
Gross burn
$95,000
per month
Net burn
$65,000
per month
Cash hits zero
Not in 5 yrs
within 5 years
Break-even
Month 25
revenue ≥ expenses

Cash in the bank

  • Cash
$0$648K$1.3MNowM6M12M18M24M30

Revenue vs expenses

  • Revenue
  • Expenses
$0$93K$186.1KNowM6M12M18M24M30Break-even · M25

✂ Cut expenses 10%: you already make it past five years at these rates.

Month-by-month model
MonthRevenueExpensesCash at month end
1$30,000$95,000$1,135,000
2$31,800$95,950$1,070,850
3$33,708$96,910$1,007,649
4$35,730$97,879$945,500
5$37,874$98,857$884,517
6$40,147$99,846$824,818
7$42,556$100,844$766,529
8$45,109$101,853$709,785
9$47,815$102,871$654,729
10$50,684$103,900$601,514
11$53,725$104,939$550,300
12$56,949$105,988$501,260
13$60,366$107,048$454,578
14$63,988$108,119$410,447
15$67,827$109,200$369,074
16$71,897$110,292$330,679
17$76,211$111,395$295,494
18$80,783$112,509$263,769
19$85,630$113,634$235,765
20$90,768$114,770$211,762
21$96,214$115,918$192,058
22$101,987$117,077$176,968
23$108,106$118,248$166,826
24$114,592$119,430$161,988
25$121,468$120,625$162,831
26$128,756$121,831$169,756
27$136,481$123,049$183,189
28$144,670$124,280$203,579
29$153,351$125,523$231,407
30$162,552$126,778$267,181
31$172,305$128,046$311,440

60+ months of runway.

If engineering is your biggest line item, a senior contractor can ship what a 3-person team would, without the payroll.

Let's talk
01

How it works

Most runway calculators divide cash by this month's burn and stop there. That number is only right if nothing changes. Here, revenue and expenses each grow at their own monthly rate, and the model steps forward one month at a time until the cash runs out or five years pass.

gross burn = monthly expenses
net burn = monthly expenses − MRR

revenue(m) = MRR × (1 + MRR growth)^(m−1)
expenses(m) = expenses × (1 + expense growth)^(m−1) + planned hire (from its start month)
cash(m) = cash(m−1) + revenue(m) − expenses(m)

runway = the month cash(m) crosses zero, interpolated within that month

The simple version, cash ÷ net burn, is what you get if both growth rates are zero. Set them to zero and the two answers match.

02

Worked example

A seed-stage SaaS with $1,200,000 in the bank, spending $95,000 a month, at $30,000 MRR growing 6% a month while costs creep up 1% a month. These are the calculator's defaults.

Worked example results
MeasureValue
Gross burn (month 1)$95,000
Net burn (month 1)$65,000
Naive runway (cash ÷ net burn)18.5 months
Modelled runwaymore than 60 months
Break-even monthMonth 25
VerdictDefault alive

The naive formula says this company has about 18 months. Growth changes the picture: revenue catches expenses in month 25, before the money runs out. Drop MRR growth to 3% in the calculator and watch the verdict flip.

03

Default alive or default dead

The phrase comes from Paul Graham's essay Default Alive or Default Dead?. His point is that many founders don't know which one they are, and the answer decides what to do next. A default alive company can choose when to raise. A default dead company has to raise, on whatever terms it can get, or change course now.

The verdict above is that test, run with your numbers. It assumes your growth rates hold, which is the weakest part of any forecast. Treat it as a direction, and re-run it every month with actuals.

04

Ways to extend runway

  • Collect cash earlier: offer annual plans with a discount, invoice up front.
  • Audit software and cloud spend. Unused seats and idle resources add up quietly.
  • Push planned hires back a quarter and model the difference with the planned-hire option.
  • Replace open-ended team costs with fixed-scope contracts for well-defined work.
  • Raise prices for new customers. It moves MRR growth without moving expenses.
05

Questions founders actually ask

What's the difference between gross burn and net burn?
Gross burn is everything you spend in a month. Net burn is what you spend minus what comes in. Runway is calculated on net burn, because revenue offsets spending. Investors look at both: gross burn shows how big the machine is, net burn shows how fast it eats cash.
How many months of runway should a startup have?
Common advice is to raise enough for 18 to 24 months, and to start the next raise with at least six months still in the bank, because rounds take months to close. If this calculator shows fewer than nine months, fundraising or cutting is already urgent.
How do I extend runway without layoffs?
Cut tools and infra you don't use, move annual vendor contracts to monthly or renegotiate them, offer annual plans to customers so cash arrives up front, delay planned hires, and replace part of a team with a contractor for a fixed scope. Try the 10% cut line under the chart to see what each change is worth.
Do annual prepayments count as revenue here?
Runway is about cash, not accounting revenue. If customers prepay for a year, add that cash to your bank balance and keep only the monthly-equivalent amount in MRR. Otherwise you count the same money twice.
What does default alive mean?
Paul Graham's test: assuming your expenses and revenue growth stay as they are, will you reach profitability on the money you have left? If yes, you are default alive. If not, you are default dead, and you need to raise, cut or grow faster. This calculator runs that test month by month for up to five years.
06

More from the workbench

04 · Money & fundraisingSaaS Metrics CalculatorsLTV, CAC, churn, NRR, burn multiple and more, each with the formula and benchmarks.01 · Plan & scopeMVP Cost EstimatorPick features and who builds it. Get an hour-by-hour estimate, not an agency teaser.02 · AI & LLMsLLM API Cost CalculatorYour monthly bill across Claude, GPT, Gemini and open models, side by side.

Fine print

Tools: on the house.
Engineer: by the hour.

Making your engineering budget go further is what I do: the same roadmap, shipped without the payroll of a full team.

I'm Himanshu, an AI and full-stack engineer. I build MVPs, AI agents and the growth plumbing around them for early-stage startups.

Hire me →My projects