The measure and the runway
Burn rate is the net cash an organisation consumes per period, most commonly per month. Gross burn counts all outgoings; net burn subtracts revenue and other inflows. Cash on hand divided by net burn gives runway: the months remaining before new funding, new revenue or lower spend becomes mandatory. The terms come from venture-funded companies but apply equally to any internally funded venture or programme living off a fixed allocation.
What burn tells a decision-maker that budgets do not
An annual budget describes permission; burn describes velocity, and velocity is what sets the real decision calendar. A venture with ten months of runway must conclude its next funding conversation in perhaps six, which means the evidence that conversation depends on must exist in four. Read this way, burn is a discipline question rather than merely a cost question: each month of spend is buying information, progress or option value, and the decision-preparation test is whether anyone can say which, and how much. Two ventures with identical burn can be in opposite conditions, one purchasing learning at a fair price, the other purchasing time to avoid a verdict.