Burn Rate Calculator

This Burn Rate Calculator helps you estimate how quickly your business is using cash each month. It separates gross burn, which is your monthly operating spend, from net burn, which is the amount of cash the business actually loses after revenue is included.

Burn rate matters because cash rarely runs out suddenly. It usually runs out predictably, one month at a time. A founder who understands burn rate can see whether the company has enough time to reach profitability, close a funding round, reduce costs, or change strategy before cash becomes urgent.

Use this calculator for quick planning and scenario checks. For board reporting, investor updates, or financing decisions, compare the result with your accounting records, bank balances, committed liabilities, tax obligations, and cash flow forecast.

Imagine a startup has £500,000 in the bank. It spends £50,000 per month on salaries, software, hosting, contractors, rent, and marketing. If the company currently has no revenue, its gross burn and net burn are both £50,000 per month.

In that case, runway is simple: £500,000 divided by £50,000 gives 10 months of runway. That does not mean the company should wait 10 months before acting. If fundraising takes three to six months, the practical decision window is much shorter.

Now suppose the same startup generates £15,000 per month in revenue while spending £50,000. Gross burn remains £50,000, but net burn falls to £35,000 per month. With £500,000 in cash, that gives about 14.3 months of runway before allowing for tax timing, working capital, one-off costs, or late customer payments.

Burn rate is one of the first numbers investors, lenders, and finance teams look at because it connects ambition to survival. A company can be growing quickly and still be fragile if its cash usage is too high for the runway available. A company can also have modest revenue today but be in a strong position if burn is controlled and the path to profitability is realistic.

From an investor perspective, burn rate helps answer three questions: how long the current funding lasts, whether spending is producing meaningful progress, and whether the next funding round is being raised from strength or desperation. The same burn can look disciplined or dangerous depending on customer growth, retention, gross margin, product milestones, and the fundraising environment.

A dangerous burn rate is not just a large monthly number. It is a burn rate that leaves too little time to respond. Many founders treat six months of runway as a warning zone and three months as urgent, especially if the business depends on external funding. The safer threshold depends on the company, but the direction of travel matters: falling runway needs attention before it becomes a crisis.

Reducing burn rate does not always mean cutting everything. The aim is to protect the spending that creates durable value and reduce the spending that does not. Start by separating fixed commitments from flexible costs. Payroll, rent, annual software contracts, and debt payments are harder to change quickly. Marketing tests, contractors, tools, travel, and discretionary projects may be easier to adjust.

Common ways to reduce burn include delaying non-critical hiring, renegotiating software contracts, pausing low-return ad spend, shortening payment terms with customers, moving contractors to milestone-based work, reducing unused tools, and focusing the team on the products or customers most likely to generate revenue soon.

Revenue can reduce net burn just as powerfully as cost control. Improving conversion, increasing prices, collecting invoices faster, reducing churn, and moving annual customers to upfront payment can all extend runway without reducing the team. The best burn reduction plan usually combines cost discipline with a sharper revenue plan.

Burn rate confusion usually mixes gross spend with net cash outflow, or compares monthly figures to quarterly costs without aligning the period.

Enter the figures you already know from forecasts, ad dashboards, or management accounts, then read the headline output before changing multiple inputs at once.

Use it when updating investors, sizing a fundraising round, stress-testing headcount plans, or comparing cost cuts against runway extension.

If the result drives hiring, fundraising, or pricing, rerun with conservative assumptions as well as your base case.

If you spend £80,000 per month and bring in £25,000 revenue, net burn is £55,000 — the figure that actually shrinks cash each month before financing.

Change one lever at a time — price, variable cost, burn, cash balance, or funnel volume — to see which assumption moves the outcome most.

Compare the calculator output to a recent month of real data; material gaps usually trace to misclassified costs or mismatched time periods.

Re-run after major decisions land — new pricing, a campaign scale-up, or a headcount change — because static estimates go stale quickly.

Mixing monthly and annual figures, or folding one-off costs into recurring burn, is the fastest way to misread runway and break-even targets.

Optimistic conversion or sales volume assumptions can make a plan look viable on paper while cash still runs down in reality.

One-time items, deferred revenue, tax payments, and inventory purchases can distort a simple monthly average. Reconcile with your cash-flow statement before major decisions.

This page should target burn rate calculator, gross burn rate, net burn rate, monthly burn rate, and startup burn rate searches.

It calculates gross burn from monthly operating expenses and net burn after monthly revenue. It does not build a cash-flow statement, model deferred revenue, working capital, tax timing, debt repayments, inventory purchases, or fundraising scenarios.