What is the difference between startup Gross Burn and Net Burn?

Gross Burn is the total absolute cash paid out each month (payroll, rent, software). Net Burn is Gross Burn minus total monthly cash collections. Runway is always calculated using Net Burn.

How do convertible notes and SAFE injections affect runway?

SAFE or convertible note proceeds immediately increase your cash balance without altering operating expenses, directly expanding your runway runway divisor.

Venture & Early Stage•Recommended Target: 18–24 months

Startup Runway Calculator

Venture-backed and early-stage startups operate in high-growth, cash-negative environments. Accurate runway calculations prevent premature fundraising fire drills and give founders clear visibility into when they must reach milestone metrics or close their next round.

Industry Benchmark Guidance (18–24 months):In cautious venture capital climates, early-stage startups should maintain 18 to 24 months of runway after raising. It typically takes 4 to 6 months to run an institutional fundraise, leaving 12 to 18 months of heads-down product iteration and customer acquisition before you must hit the road again.

Quick PresetsClick to test scenario

Current Available CashLiquid reserves

Monthly Revenue

Monthly ExpensesGross Burn

Monthly Revenue Growth

Monthly Expense Growth

One-Time Upcoming Expense

Occurs in Month

Additional Funding Cushion

Arrives in Month

Estimated Cash Runway

Calculated Runway

13.7 months

Healthy: You have 13.7 months of runway (November 2027).

Estimated Cash Depletion:November 2027

Net Burn:$50,000/mo

Net Monthly Burn

$50,000

Expenses − Revenue

Gross Burn (Expenses)

$65,000

Total monthly outlays

Current Cash

$750,000

Liquid reserves balance

Break-Even Target Revenue

Monthly sales required to eliminate cash burn entirely: $65,000/month

Gap: +$50,000/mo

Projected Cash Remaining

Based on trajectory

After 3 Months$577,788

After 6 Months$419,592

After 12 Months$92,175

Projected Cash Trajectory (24-Month Horizon)

Real-time projection showing monthly cash reserves over time.

Cash Balance

Zero Cash Threshold

Hover or tap any month marker to inspect exact projected cash balance, revenue, and burn for that period.

“What If?” Scenario Modeling

Test how cutting burn, expanding sales, or raising capital extends your survival timeline.

Reduce expenses by 5%+1.1 mo

Save $3,250/mo (new expenses: $61,750/mo)

Runway:

13.7 mo14.8 months

Reduce expenses by 10%+2.4 mo

Save $6,500/mo (new expenses: $58,500/mo)

Runway:

13.7 mo16.1 months

Reduce expenses by 20%+7.1 mo

Save $13,000/mo (new expenses: $52,000/mo)

Runway:

13.7 mo20.8 months

Financial Calculation Methodology & Transparency

How the Runway Calculator Works: Mathematical Model & Assumptions

1. Static Cash Runway Formula

For businesses with steady revenue and predictable overhead, runway is determined by dividing liquid cash reserves by net monthly cash deficit:

Runway (months) = Available Cash ÷ Net Monthly Burn

2. Gross Burn vs. Net Burn

Gross Burn: Total cash disbursed each month (payroll, contractors, hosting, rent, utilities).
Net Burn: Gross monthly expenses minus total monthly cash revenue collections.
Break-Even: When Net Burn $\le$ $0$, cash runway is mathematically sustainable or infinite.

3. Dynamic Growth Projections & Interpolation

When revenue growth or expense inflation rates are enabled, the engine calculates month-by-month compound flows up to 60 months:

Ending Cash(m) = Beginning Cash(m) + Revenue(m) - Expenses(m)

Fractional Month = Beginning Cash(depletion) ÷ Monthly Net Burn

We linearly interpolate the exact day/fraction when cash reaches $0, avoiding arbitrary rounded whole months.

4. Client-Side Privacy Guarantee

Every financial computation executes exclusively inside your local browser runtime. No financial balances, revenue figures, or payroll numbers are sent to any remote server or database.

Primary Cost Drivers

Major Burn Drivers for Startups

Engineering & Product Payroll

Salaries, health benefits, payroll taxes, and recruiting commissions typically comprise 70–85% of total operating expenses for early tech startups.

Cloud Infrastructure & AI APIs

Compute clusters, vector databases, LLM inference API costs, and third-party SaaS tooling that scale aggressively with user adoption.

Customer Acquisition Costs (CAC)

Paid search, outbound sales tooling, demo SDRs, and channel experimentation before achieving predictable unit economics.

Actionable Levers

How to Extend Startups Runway

Institute a Dynamic Hiring Freeze

Defer non-essential general and administrative (G&A) hires and align every new headcount strictly with revenue generation.

Incentivize Annual Upfront Contracts

Offer enterprise prospects a 15–20% discount for paying 12 months upfront, transforming receivables into instant non-dilutive working capital.

Audit Software Tooling & Cloud Tiers

Prune unused seat licenses, renegotiate AWS/GCP startup credits, and eliminate redundant developer tooling to shave 5–15% off gross burn.

Worked Calculation: Seed-Stage AI Developer Tool

Starting Cash$750,000

Monthly Cash Inflow$15,000

Monthly Cash Outflow$65,000

With $750,000 in bank deposits and $65,000 monthly expenses offset by $15,000 monthly recurring revenue, net monthly burn is $50,000. Without growth, runway is exactly 15.0 months ($750,000 ÷ $50,000). Factoring in 8% monthly revenue growth against modest 3% expense creep extends true runway to 16.8 months.

Frequently Asked Questions: Startups Runway

Common questions and financial benchmarks for startups.

You should initiate institutional fundraising when you have 6 to 9 months of runway remaining. If negotiations take 4 to 5 months, closing at the 3-month mark prevents investor leverage from forcing disadvantageous down-rounds or punitive term sheets.