Runway & Burn Modeler.

Runway is the number of months a startup can operate before running out of cash. There are three useful definitions, not one.

Cash runway is current cash divided by current monthly burn. It assumes burn stays flat, which it almost never does.

Forward burn runway accounts for planned hires, contract renewals, and known one-time payments. This is the realistic number.

Decision runway is the time remaining before fundraising must begin, working backwards from the cash-out date by the typical 3-6 month fundraising cycle. This is the number that should drive your calendar.

Gross burn is total monthly cash outflow: salaries, rent, tools, marketing, infrastructure. Net burn is gross burn minus any revenue collected during the same period.

For venture-stage companies, net burn is what matters for runway. The Runway & Burn Modeler computes net burn month by month so seasonal swings and hiring waves are visible. Trailing-average burn (a single number) hides the trough.

Burn multiple is net new burn divided by net new ARR over a period (typically a quarter or trailing twelve months). It measures capital efficiency: how much cash you burn to generate each new dollar of recurring revenue.

Benchmarks (coined by David Sacks of Craft Ventures):

Under 1.0: excellent. 1.0-1.5: great. 1.5-2.0: good. 2.0-3.0: suspect. Over 3.0: a red flag for Series A investors.

If you do not have revenue yet, burn multiple is not meaningful. Focus on hitting milestones efficiently and the metric becomes relevant later.

Institutional fundraising cycles take 3 to 6 months from first outreach to cash in the bank. Working backwards: start active fundraising when forward burn runway hits 6 months, not when you hit 3.

Decision runway tracks this directly. When decision runway hits zero, fundraising must already be underway. Tight runway leads to bad term sheets and weak negotiating positions.

The lowest cash point is the trough in your monthly cash trajectory over the forecast period. It often happens months before the actual cash-out date, driven by an annual contract renewal, a large one-time payment, or a seasonal revenue dip.

Investors look at this in diligence. Founders rarely do. A company with $1M of cash, $80K/month burn, and a $200K renewal in month six does not have twelve months of runway. It has a cash dip that goes dangerously close to zero in month seven.

Basic runway calculators divide current cash by trailing-average monthly burn. That number is wrong for two reasons.

One. Trailing burn ignores forward changes: every planned hire, every renewal, every one-time payment that has not happened yet.

Two. It ignores the fundraising-cycle lag. You cannot start a raise at month 12 of an 18-month runway and expect to close before zero.

The Runway & Burn Modeler computes three runways simultaneously, surfaces the lowest cash point, and computes burn multiple: the metrics Series A investors actually run.

Rough benchmarks for 2025-2026:

Pre-seed (under $1M raised): burn of $30-60K/month. Three to five-person teams.

Seed ($1.5-3M raised): burn of $80-180K/month. Six to twelve-person teams.

Post-seed / pre-A ($3-6M raised): burn of $150-300K/month. Twelve to twenty-person teams.

Series A ($8-15M raised): burn of $300-600K/month. Twenty to forty-person teams.

These are bands, not prescriptions. Capital-intensive sectors run higher. AI infrastructure runs higher still. The right question is not "what is normal" but "does this burn produce the milestones we need before the next raise."