Burn rate is the single number that tells a founder how long the business has before something has to change. Tracking it correctly is more useful than almost any other financial discipline at the startup stage — and yet most founders calculate it slightly wrong, get a number that is either too pessimistic or too optimistic, and either panic prematurely or run out of cash with weeks of warning instead of months.
This guide gives you the calculator (use the inputs in the section below to compute yours), the difference between gross and net burn, benchmark numbers by stage, and the four triggers that mean it is time to cut spend or raise money. The framing is built for $1M–$50M SaaS and tech businesses, but the math works for any cash-burning business.
How to calculate burn rate
There are two formulas and you need both.
Gross burn = Total cash operating expenses per month
Add up everything you spent in a given month: payroll, contractors, rent, software, marketing, professional services. Exclude one-time non-operating expenses (a legal settlement, a financing fee). Exclude depreciation and amortization (those are not cash). The result is gross burn — the total cash going out the door per month to run the business.
Net burn = Gross burn − Cash revenue collected per month
Subtract cash actually received from customers in the month. The result is net burn — the actual cash position deterioration per month, which is the number that drives your runway.
The two numbers diverge whenever you have any revenue at all. A pre-revenue startup has equal gross and net burn. A SaaS business with $200K MRR has gross burn that might be $400K but net burn of $200K. Investors and boards usually want to see both, with net burn as the headline.
The simple calculator
Plug your numbers into the four-line version:
Total monthly operating expenses $______ (A)
Total monthly cash revenue collected $______ (B)
Net burn (A − B) $______ (C)
Current cash balance $______ (D)
Runway in months (D ÷ C) ______ months
For a more rigorous calculation, average the last three months instead of using a single month. Single-month numbers are noisy because of timing issues — a quarterly insurance payment, a delayed customer collection — and can mislead you in either direction.
Gross burn vs net burn: when to use which
Gross burn matters when you are stress-testing. If revenue stops tomorrow (a major customer churns, a pipeline deal falls through), how long does the business last? Runway against gross burn is the answer to that question. It is the worst-case version of the same calculation.
Net burn matters for normal operating decisions. Given that revenue is roughly continuing at current levels, how long does the business last? Net burn is the right number for hiring decisions, marketing spend decisions, and most board conversations.
A useful discipline: report both numbers every month, then make decisions against net burn but pressure-test important decisions against gross burn. If you are about to make a hire that flips your runway-against-gross-burn from 18 months to 9 months, that is information worth having even if the runway-against-net-burn looks comfortable.
Where founders most often get this wrong
Three patterns recur in the books we have reviewed for early CentSight users.
Confusing cash collected with revenue earned. A customer who signed a $120,000 annual contract and paid up front did not generate $120,000 of cash revenue this month for burn-rate purposes — well, they did for cash-collected, but most founders accidentally mix accrual revenue (the $10,000 monthly recognition) with cash receipts ($120,000 in month one, then $0 for eleven months). Burn rate uses cash. Get the books right and the formula falls out.
Forgetting to include capitalized costs. A founder who capitalizes a software development cost or a piece of equipment removes it from the income statement but the cash still left the bank. Burn rate uses cash, so capitalized expenses count. Same logic for prepaid expenses — a $24,000 annual SaaS prepayment hits cash burn in the month you paid it, not the twelve months it covers.
Including non-cash items. Depreciation, amortization, and stock-based compensation hit the income statement but are not cash. They should not be in your burn calculation. The clean way to handle this is to start from the cash flow statement, not the P&L.
A clean accrual ledger usually fixes all three of these. If you do not have a clean ledger, building one is more important than computing burn — the burn rate from a messy ledger is just a confidently presented wrong number.
Original Data: Burn benchmarks by stage
After looking at burn rates across early CentSight users and publicly disclosed data from several SaaS companies in the $1M–$50M revenue range, here are the rough benchmark bands by funding stage. These are not targets — they are descriptions of what is typical. A business below the band may be capital-efficient or under-resourced; a business above the band may be aggressively scaling or in trouble.
| Stage | Typical net burn | Headcount | Runway target | |---|---|---|---| | Pre-seed | $25K – $80K/mo | 2–6 | 18+ months | | Seed | $100K – $250K/mo | 8–20 | 18–24 months | | Series A | $300K – $700K/mo | 25–60 | 18 months | | Series B+ | $600K – $1.5M/mo | 60–150 | 12–18 months |
A few things to notice. The runway target gets shorter at later stages, not longer — late-stage companies are expected to be closer to profitability and have more options for bridge financing if needed. Headcount scales roughly proportional to burn; payroll is typically 60–75% of total operating expense in tech businesses, and the burn-per-employee number stays surprisingly stable across stages at $8K–$12K per employee per month all-in.
The "when to worry" thresholds, in our experience working with founders, fire when:
- Runway drops under 12 months. This is the standard warning line. Below 12 months, fundraising becomes the dominant priority and operating decisions get more conservative.
- Net burn grows faster than revenue for two consecutive quarters. Either you are investing into a real growth opportunity (good, if it is producing) or your cost structure is getting out of step with the business (bad, almost always).
- Gross burn rate is more than 4× revenue at Series A or later. At earlier stages this is normal. At Series A and later, it usually means the unit economics or the go-to-market motion has not started working yet.
- Revenue stops growing while burn keeps growing. The clearest sign that the cost structure was built for an assumed growth rate that the business is not actually delivering.
If any of these fire, the right move is rarely to panic. It is to run a serious review of the underlying numbers and understand whether the issue is temporary (a slow quarter, a hiring lag) or structural (a unit economics problem, a market issue). The runway planning page covers the second-step analysis in more depth.
Worked example: a four-stage burn trajectory
Take a hypothetical SaaS business and watch how burn changes as it grows.
Pre-seed (18 months in): $0 ARR, 4 employees, $55K/mo gross burn, $55K/mo net burn. $1M raised. Runway: ~18 months.
Seed (12 months later): $400K ARR ($33K/mo cash revenue), 12 employees, $180K/mo gross burn, $147K/mo net burn. $4M raised. Runway: ~27 months.
Series A (18 months later): $2.4M ARR ($200K/mo cash revenue), 35 employees, $520K/mo gross burn, $320K/mo net burn. $12M raised. Runway: ~37 months.
Series B+ (24 months later): $8M ARR ($667K/mo cash revenue), 80 employees, $1.1M/mo gross burn, $433K/mo net burn. $28M raised. Runway: ~65 months.
Two patterns worth pulling out. Gross burn grows roughly 5× across each transition; revenue grows faster than that, so net burn grows more slowly than gross burn. By Series B+, net burn is growing slowly enough that the runway looks comfortable — but the runway-on-gross-burn (without revenue) is roughly half of net-burn runway, and that is the number that matters if revenue ever falters.
This is why mature companies care more about gross burn than seed-stage companies do. At seed stage, gross and net burn are nearly equal; the distinction is academic. At growth stage, they can differ by 2–3× and the gap is where your stress-test scenarios live.
What to do when your burn is too high
Three categories of moves, in roughly the order most founders should consider them.
Increase efficiency before cutting. Renegotiate annual SaaS contracts for monthly. Pause optional consulting spend. Tighten T&E. These produce 5–15% reductions in gross burn without affecting the team. Easy wins worth doing first.
Cut non-essential headcount. Roles that were hired for an assumed scale that has not arrived. The hardest call to make and the most important. The cost of getting this right is high; the cost of getting it wrong (cutting a key contributor, demoralizing the team) is higher.
Cut growth investment. Marketing spend, R&D projects that have not started producing, expansion into new segments. Often the right move at the margin but slow to take effect — marketing cuts produce burn savings immediately but pipeline impact 3–6 months later.
The order matters because the moves cascade. Efficiency cuts buy you a few months. Headcount cuts produce the largest single reduction but are slow and emotionally expensive. Growth investment cuts are faster but mortgage the future.
How CentSight tracks burn rate
CentSight pulls cash flow data directly from your QuickBooks Online ledger and Plaid-connected bank accounts and computes both gross and net burn rate as a 3-month rolling average, updated daily. The platform also tracks the four warning triggers above and surfaces them in the daily summary, so you do not have to remember to look.
Burn rate is one of the standard reports in the management reporting cadence. For a deeper look at how the forecast feeds the runway calculation, AI cash flow forecasting covers the modeling layer that projects burn forward. For the broader category, AI CFO covers the full AI CFO product surface. And startup finance is the founder-stage hub that ties burn, runway, and fundraising together.
FAQ
What's the difference between burn rate and runway? Burn rate is the rate at which cash leaves the business per month. Runway is how many months of burn your current cash will cover. Runway = Cash ÷ Monthly Net Burn.
Should I use gross or net burn rate? Both. Use net burn as your default for operating decisions. Use gross burn for stress-testing and worst-case planning. Report both to your board.
Is a higher burn rate always bad? No. A high burn rate at a fast-growing company is normal and often desirable. The question is whether burn is growing in line with revenue and whether the unit economics are healthy. Burn in isolation tells you almost nothing.
How does revenue affect burn rate calculations? Revenue reduces net burn dollar-for-dollar to the extent it is collected in cash in the same period. A $100K MRR SaaS business with $500K of monthly operating expenses has $500K gross burn and $400K net burn.
How often should I track burn rate? Monthly, with a 3-month rolling average to smooth out timing noise. Founders running tight should check weekly. Anything more frequent than weekly is over-tracking and tends to produce panic moves on noise.
What's a good burn rate for a SaaS startup? There is no single answer — it depends on stage, ARR, and growth rate. The benchmark table above gives typical bands by stage. The more useful question is "is my burn rate consistent with the runway I need to hit my next milestone?"
Can I include accounts receivable in my burn rate calculation? No. Burn rate is a cash measure. AR is on the balance sheet, not in your operating cash flow. If you want to estimate the cash impact of expected AR collections, that is a separate forecast — built into a 13-week cash flow.
Related resources
- Runway planning — how to set runway targets and time fundraising
- AI cash flow forecasting — the forecasting layer that projects burn forward
- AI CFO — the broader AI CFO category
- Startup finance — the founder-stage finance hub
- Management reporting — where burn rate fits in the monthly reporting cadence
Track your burn automatically
Burn rate calculations are simple in theory and miscalculated in practice — usually because the books are not clean enough to produce a reliable cash number, or because the founder is mixing cash and accrual data without realizing it. CentSight pulls directly from your accounting and banking systems, applies a clean accrual treatment, and generates daily-updated gross and net burn rates with the runway implications. Join the waitlist to see your burn rate calculated correctly for the first time.
About the author: Gerald Hetrick is the founder and owner of CentSight, the AI CFO platform for $1M–$50M SaaS and tech businesses.
