TL;DR

Runway is the number of months a company can operate before running out of cash. Most investors want to see 18+ months of runway post-financing. Founders should start fundraising when they have 6–9 months of runway remaining.

Key Definitions

Gross burn rate: Total cash spent per month

Net burn rate: Cash spent minus cash received (gross burn - revenue)

Runway: Current cash balance ÷ Net monthly burn rate = Months of runway

Runway Calculation Example

  • Cash balance: $1,200,000
  • Monthly gross burn: $200,000
  • Monthly revenue: $50,000
  • Net burn: $150,000
  • Runway: $1,200,000 ÷ $150,000 = 8 months

When to Start Fundraising

Start when you have 6–9 months of runway remaining. Fundraising takes 3–6 months.

Never fundraise from desperation — it weakens your negotiating position.

How to Extend Runway

Revenue Acceleration: Annual prepayment discounts (10–20%), accelerate sales cycles, expand existing accounts

Cost Reduction: Defer non-essential hires, renegotiate vendor contracts, reduce cloud infrastructure costs

Non-Dilutive Capital: Revenue-based financing (Clearco, Capchase), government grants, R&D tax credits, SBIR/STTR (US), CONACYT (Mexico)

The Default Alive Concept (Paul Graham)

At your current growth rate and burn rate, will you reach cash flow breakeven before your runway ends?

If yes: "Default alive" — position of strength

If no: "Default dead" — must raise capital or change trajectory

Key Takeaways

Key Takeaways
  • Runway = Cash balance ÷ Net monthly burn rate.
  • Start fundraising with 6–9 months of runway remaining.
  • Annual prepayment discounts are the fastest way to extend runway.
  • "Default alive" means you reach profitability before running out of cash without new capital.
  • Never fundraise from desperation — it weakens your negotiating position.