Free Tool

Runway Calculator

Estimate how long your cash will last

Total cash currently available in your accounts
Total monthly operating expenses before revenue
Current monthly recurring revenue from all sources
Expected month-over-month revenue growth rate
Understanding

What is Cash Runway?

Cash runway is the number of months a startup can continue operating before it runs out of money. It is arguably the most important operational metric for early-stage companies because running out of cash is the top reason startups fail.

Key Terms

Cash Runway

The estimated number of months remaining before a company exhausts its cash reserves at the current spend rate.

Burn Rate

The monthly rate at which a company spends cash, used as the denominator when calculating runway.

Burn-Out Date

The projected calendar date when cash will reach zero if current spending and revenue trends continue unchanged.

Revenue Growth

The rate at which monthly revenue is increasing, which can extend runway by reducing net burn over time.

Formulas Used

Simple Runway
Runway = Cash Balance ÷ (Monthly Burn − Monthly Revenue)

Divide available cash by your net monthly burn to get a basic runway estimate in months.

With Growth
Simulated month-by-month: Revenue grows by Growth % each month until cash runs out

A dynamic model that projects runway by increasing revenue each month according to a growth rate, providing a more realistic timeline.

How it works

Three simple steps

01

Enter your cash position

Input your current cash balance, monthly expenses, and monthly revenue.

02

Calculate your runway

The calculator divides your cash by net monthly burn to determine months of runway remaining.

03

Plan your next steps

Review your runway timeline and see how changes in spending or revenue affect your deadline.

Use cases

Built for founders like you

Post-funding planning

Understand exactly how long your latest round will last at current spend levels.

Scenario modeling

Compare runway under different hiring plans, marketing budgets, or revenue assumptions.

Board updates

Provide clear runway projections in monthly board reports and investor updates.

Why runway planning is critical

Runway is the number of months a startup can continue operating before running out of cash. It is calculated by dividing your current cash balance by your net monthly burn rate. This single number dictates your strategic timeline.

Running out of runway is the number one reason startups die. According to CB Insights, 38% of startups fail because they run out of cash or fail to raise new capital. Knowing your runway lets you plan fundraising, hiring, and growth investments on a realistic timeline.

Smart founders track runway weekly and model multiple scenarios — best case, base case, and worst case. This lets you make proactive decisions rather than reactive ones when cash gets tight.

FAQ

Common questions

How is runway calculated?+
Runway = Current Cash Balance / Monthly Net Burn Rate. If you have $500K and burn $50K per month net, you have 10 months of runway.
When should I start fundraising based on runway?+
Start fundraising when you have 9-12 months of runway left. Raising typically takes 3-6 months, so this gives you a buffer if the process takes longer than expected.
How do I extend my runway without raising?+
Reduce expenses, accelerate revenue, negotiate longer payment terms with vendors, or consider revenue-based financing. Even small improvements compound over several months.

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