Cash Burn Rate Calculator - Free Online Calculator

Cash burn rate is the speed at which a company spends its cash reserves to fund operations before accounting for new inflows. For startups and any business investing ahead of profit, burn is one of the few metrics that translates directly into survival: paired with the cash sitting in the bank, it tells you how many months remain before the account hits zero if nothing changes. Investors, boards, and lenders rarely debate whether burn matters; they debate whether the spend is buying durable growth, whether the team can execute inside the runway window, and whether the next financing or profitability milestone is realistic. Gross burn describes total cash going out the door for operations—payroll, rent, software, marketing, and everything else you pay monthly before you net in customer receipts. Net burn subtracts recognized monthly revenue (or cash receipts, depending on how you define the metric internally) from those expenses. When revenue exceeds expenses, net burn can be zero or negative, which means the business is cash-flow positive at that run rate. Runway is simply the ratio of cash on hand to net burn when net burn is positive: it answers “how long do we have?” in month-equivalents. Zero-cash date projects that horizon onto a calendar, assuming the current net burn stays constant—a deliberate simplification that still helps teams align fundraising and cost decisions. SynthQuery’s Cash Burn Rate Calculator is built for fast, transparent arithmetic you can explain in a board meeting. You can work from actual bank balances across a period—ideal when you want the net burn implied by real cash movement—or from monthly revenue and expense lines when your finance model already separates them. The page shows gross burn, net burn, runway months, and a projected zero-cash date, plus charts that visualize declining cash and compare gross versus net burn. Reset clears inputs, Copy results exports a plaintext memo, and nothing leaves your browser for the math.

The calculator exposes two input paths because operators think in both “what did the bank statement do?” and “what does our P&L say each month?” In the period balances tab, you enter starting cash, ending cash, and the number of months in the window. The tool divides the change in cash by months to estimate average net burn. Gross burn is displayed equal to that figure in this mode because any revenue you collected is already embedded in the cash trajectory—you are seeing the net of everything that hit the account. That convention keeps the worksheet honest: if you need gross expenses separate from revenue, switch to the revenue and expenses tab. In the revenue and expenses tab, gross burn is monthly expenses and net burn is monthly expenses minus monthly revenue. You also enter cash on hand, which anchors runway and the zero-cash projection. Runway appears only when net burn is strictly positive; if you are breaking even or generating cash at that monthly cadence, runway is not a finite number and the interface shows an em dash rather than pretending a distant zero date. Charts reinforce the story: a line chart plots remaining cash month by month until it reaches zero when net burn is positive, with a runway marker for orientation, and a bar chart contrasts gross and net burn side by side so you can see how much revenue is offsetting operating spend. Mobile layouts stack the same fields and outputs with large tap targets and monospace figures for quick scanning before a call. Copy results includes the canonical URL and FIN-022 tag so pasted summaries trace back to this page. The projection uses a linear model—no seasonality, no lumpy fundraising, no receivables timing—which matches how burn is taught and how many early dashboards are built, while remaining easy to sanity-check against a fuller cash flow model when stakes rise.

Let S be starting cash, E ending cash, and T the number of months in the period. In the balance method, average monthly net burn is (S − E) / T. Positive values mean cash declined over the period; negative values mean cash grew. Gross burn is shown equal to that average in this mode because revenue effects are already folded into S and E. Runway, when net burn is positive, is E divided by net burn, interpreted as months of cushion at the observed spend rate. The zero-cash date applies the same runway length forward from the calculation date using a fractional-month adjustment so partial months are not discarded silently. In the revenue and expenses method, gross monthly burn G equals monthly expenses, and net monthly burn N equals monthly expenses minus monthly revenue. Runway is cash on hand C divided by N when N is greater than zero. If N is less than or equal to zero, runway is undefined in the finite sense because cash is not depleting at that monthly cadence. Charts plot cash balances as max(0, C − m · N) for month indices m until zero is reached or a display cap is hit. Bar charts read G and N directly. Rounding in copied text follows locale formatting; tie to the penny against your ledger before contractual decisions.

Startup finance leads use burn and runway in weekly operating reviews to decide whether hiring plans, vendor contracts, or campaign spends still fit the treasury. A single transparent calculator session prevents arguments about hidden spreadsheet cells when everyone can see the same definitions on one page. Fundraising timing benefits from explicit runway math: many teams trigger outreach when cash falls below a comfort threshold measured in months; this tool makes that threshold numeric and easy to recompute after each close. Board reporting often includes a slide with gross burn, net burn, and runway, sometimes alongside MRR or ARR. Export Copy results into your packet draft so assumptions are traceable. Cost-control initiatives—renegotiating cloud contracts, deferring hires, or trimming programs—can be translated into a lower monthly expense line in the revenue and expenses tab to preview runway extension without building a full model. For bootstrapped businesses, negative or zero net burn is a celebrated outcome; the interface surfaces when linear runway is not applicable so you do not misinterpret a healthy cash position. Enterprise innovation groups and nonprofit project teams borrow the same vocabulary when they run internal “venture” budgets. Agencies estimating how long a retainer covers overhead can approximate net burn against reserves between large client payments. Educators teaching entrepreneurship can assign students to reconcile the balance method with the P&L method using a fictional case file, then compare to SynthQuery outputs. None of these workflows replace audited statements or banking covenants, but they accelerate shared understanding before you invest time in heavier tools.

Start with the tab that matches the data you have in front of you. If you are pre-revenue or only want the burn implied by your treasury, open Period balances. Pull starting cash from your bank balance on the first day of the measurement window and ending cash from the last day—use true cash, not accrual balances from accounting unless your policy is to manage the business on an accrual view. Enter the length of the window in months; partial months are allowed if you use a decimal (for example, thirteen weeks is about three months). Click Calculate to read average monthly net burn, gross burn (mirroring net in this mode), runway based on ending cash, and the zero-cash date measured from today. If you are post-revenue and maintain a simple monthly operating model, switch to Revenue and expenses. Type monthly revenue as you define it for internal KPIs—often cash receipts or recognized subscription revenue, but be consistent with how you report to your team. Enter monthly expenses as total operating cash spend for a typical month, excluding extraordinary one-offs if you want a steady-state story, or include them if you want a conservative stress case. Add cash on hand as the liquid balance you are willing to apply to operations. Calculate to see gross burn as expenses, net burn as the gap after revenue, runway, and zero-cash date. After the first pass, scenario-test deliberately. Raise or lower marketing spend in the expense field to see how runway moves. Increase revenue modestly to model a launch quarter. Compare results to your last three bank statements; if the balance method and the P&L method diverge wildly, investigate timing differences such as annual prepayments, payroll cycles, or inventory builds. Use Reset when you want the teaching defaults back, and Copy results when you need to paste into email, Notion, or a board appendix. Pair outputs with your fundraising calendar: runway months should connect to when you expect to close the next tranche or hit profitability, not exist in isolation.

Linear burn assumptions ignore seasonality, biweekly payroll spikes, annual renewals, and receivables delays. Fundraising inflows, tax refunds, and one-time asset sales are not modeled here; if you expect them, adjust cash basis manually or use a fuller cash flow forecast. Multicurrency teams should convert to a single reporting currency before typing figures. Net burn from bank balances can be distorted by financing proceeds or debt service—sanitize the window or annotate copied summaries when explaining to investors. A “good” burn rate is context-dependent: venture-backed growth companies may tolerate high gross burn while hitting milestones, while bootstrappers target zero or negative net burn early. The metric is not moral; it is informational. Reconcile this calculator with your CFO or accountant before making layoffs, signing leases, or issuing forward guidance. For acquisition efficiency alongside burn conversations, use the CAC Calculator; for paid media envelopes, use the PPC Budget Calculator on SynthQuery.