Comparison
Gross Burn vs Net Burn: Key Differences Explained
Gross burn is total monthly cash expenditure before accounting for revenue. Net burn is what's left after revenue offsets expenses — the actual cash consumed each month. Net burn determines real runway; gross burn reveals your cost structure. Both matter, but net burn is the number that actually controls when you run out of money.
What is Gross Burn?
Gross burn is the total cash a company spends each month across all categories — salaries, rent, infrastructure, marketing, tools, and any other operating expenses — before subtracting revenue.
Gross burn = Total monthly cash outflows
Gross burn represents your full cost structure. It's the relevant number when you're pre-revenue, and it reveals how efficiently you're deploying capital regardless of how much revenue offsets it.
Knowing gross burn helps you understand: what it costs to run the business at its current scale, which expense categories are growing fastest, and how much you'd need to cut to reduce burn significantly.
Example: A 15-person startup spends $750K/month on salaries, $100K on infrastructure, and $150K on marketing. Gross burn = $1M/month.
What is Net Burn?
Net burn is gross burn minus monthly revenue. It's the actual cash consumed from your bank account each month — the true measure of how fast you're spending down reserves.
Net burn = Gross burn − Revenue
Net burn is what determines runway. As revenue grows, net burn naturally decreases even if gross burn stays flat — which is why growing revenue is the most capital-efficient way to extend runway.
At the extreme: if revenue equals or exceeds gross burn, net burn is zero or negative — the company is cash-flow positive and has infinite runway.
Example: Same company with $1M gross burn but $400K monthly revenue. Net burn = $600K/month. At $2M in the bank, runway = $2M / $600K = 3.3 months.
Key Differences
| Feature | Gross Burn | Net Burn |
|---|---|---|
| Definition | Total monthly expenses before revenue | Monthly expenses minus monthly revenue |
| Formula | Sum of all operating expenses | Gross Burn − Revenue |
| Runway impact | Doesn't directly calculate runway | Directly determines runway (Cash / Net Burn) |
| Revenue included? | No | Yes |
| Most relevant when | Pre-revenue; evaluating cost structure | Post-revenue; evaluating actual cash consumption |
| Optimization target | Cut to reduce cost structure | Reduce by either cutting costs OR growing revenue |
| Investor context | Used to assess hiring pace and operational efficiency | Used to calculate runway and fundraising timing |
When Founders Choose Gross Burn
- →Analyzing your cost structure independently of revenue — how much does it cost to run the company?
- →Pre-revenue companies where gross and net burn are identical
- →Identifying which expense categories to cut if you need to reduce spending
- →Comparing headcount costs vs. infrastructure vs. marketing as percentages of total spend
When Founders Choose Net Burn
- →Calculating runway — how many months until you need to raise or reach profitability
- →Reporting financial health to investors and the board
- →Planning fundraising timing — when do you need to start a raise based on net burn?
- →Modeling scenarios — what does runway look like if ARR grows 20% vs. stays flat?
Example Scenario
A startup has $2M in the bank. Gross burn is $800K/month (team of 20). Revenue is $200K/month. Net burn = $600K/month. Runway = $2M / $600K = 3.3 months — dangerously low.
Option A: Cut 5 people, reducing gross burn to $600K. Net burn = $400K. Runway = 5 months — better but still tight. Option B: Close two enterprise deals, growing revenue to $400K. Net burn = $400K. Same runway, higher ARR. Option B preserves team and company value better.
Common Mistakes
- 1Using gross burn when investors ask about burn rate — they almost always mean net burn
- 2Forgetting that revenue growth extends runway without any cutting — this insight motivates focusing on sales over cost-cutting
- 3Not tracking gross burn separately — you can't identify which costs to cut if you only track net
- 4Assuming low net burn means healthy operations — a company with $50K net burn and $50K revenue has identical unit economics to one with $1M net burn and $950K revenue; the latter is at much better scale
Which Matters More for Early-Stage Startups?
Net burn is the number that drives survival decisions — it's what you track to know when to raise, when to cut, and when you're safe. Gross burn is the number that drives efficiency decisions — it's what you track to understand your cost structure and where to optimize. Both belong in every monthly financial review; neither alone tells the complete story.