Burn Rate & Runway Calculator
Calculate how fast you're spending cash and how long until you run out
Cash Position
Cash at beginning of period
Current cash balance
Measurement period
Average monthly revenue (optional)
Burn Analysis
Monthly Burn Rate
Net Burn Rate
Runway
Burn Ratio
Understanding Burn Rate
What is Burn Rate?
Burn rate is the rate at which a company spends its cash reserves before generating positive cash flow from operations. It's typically measured monthly and is critical for startups and growth-stage companies that aren't yet profitable.
There are two types: Gross Burn Rate (total monthly cash outflow regardless of revenue) and Net Burn Rate (cash outflow minus revenue). Net burn rate shows the actual rate at which you're depleting cash reserves.
Key Formulas
1. Monthly Burn Rate
Monthly Burn = (Starting Cash - Ending Cash) / Number of Months
2. Runway
Runway (months) = Current Cash Balance / Monthly Net Burn Rate
How long until you run out of money at the current spending rate.
3. Burn Multiple (Efficiency)
Burn Multiple = Net Burn / Net New ARR
How much cash you burn to generate $1 of new recurring revenue. Lower is better (<1.5x is excellent).
Example Calculation
SaaS Startup Scenario:
- • Starting Cash (Jan 1): $500,000
- • Ending Cash (June 30): $200,000
- • Time Period: 6 months
- • Monthly Revenue: $30,000 (growing)
Calculations:
- • Total Cash Burned: $500k - $200k = $300,000
- • Gross Monthly Burn: $300k ÷ 6 = $50,000/month
- • Net Monthly Burn: $50k - $30k = $20,000/month
- • Gross Runway: $200k ÷ $50k = 4 months
- • Net Runway: $200k ÷ $20k = 10 months
⚠️ Warning: With only 10 months of runway, this startup needs to raise capital within 6-8 months or achieve profitability (revenue > expenses) to avoid running out of cash.
Runway Thresholds & Risk Levels
✅ Safe: 18+ months runway
Comfortable buffer for growth experiments and strategic planning.
⚠️ Caution: 12-18 months runway
Start fundraising conversations or accelerate path to profitability.
🔥 Urgent: 6-12 months runway
Active fundraising required NOW. Consider cutting expenses.
🚨 Critical: <6 months runway
Emergency mode. Immediate layoffs, expense cuts, or bridge financing needed to survive.
Frequently Asked Questions
What's a healthy burn rate for a startup?
There's no universal "healthy" burn rate—it depends on your stage, industry, and growth strategy. However, here are general benchmarks:
- • Pre-seed/Seed ($0-2M raised): $20-50K/month burn, target 18-24 months runway
- • Series A ($2-10M raised): $100-300K/month burn, target 18-24 months runway
- • Series B+ ($10M+ raised): $500K-2M/month burn, target 12-18 months runway
The key metric isn't absolute burn rate, but burn efficiency—are you burning cash to acquire customers and grow revenue? A $500K/month burn is healthy if you're adding $1M+ ARR monthly (burn multiple <0.5x). The same $500K burn is catastrophic if you're only adding $50K ARR monthly (burn multiple 10x).
How do I reduce burn rate without killing growth?
Smart burn rate reduction focuses on efficiency, not just cutting costs:
1. Cut Low-ROI Spending (20-30% reduction potential):
- • Pause underperforming marketing channels (if CAC > 3x LTV, stop immediately)
- • Eliminate unused SaaS subscriptions (average company wastes $15K+/year on forgotten tools)
- • Renegotiate vendor contracts (10-15% savings typical with competitive bids)
- • Cut perks/benefits that don't impact retention (free lunches, expensive office)
2. Improve Unit Economics (15-25% reduction):
- • Focus on organic growth channels (SEO, referrals) vs paid ads
- • Increase prices 10-20% (test on new customers first, usually 5-10% churn vs 15-20% revenue boost)
- • Upsell existing customers (30-50% cheaper than acquiring new ones)
- • Automate manual processes (customer onboarding, support, billing)
3. Shift Fixed to Variable Costs (10-20% reduction):
- • Convert salaried roles to contractors/freelancers where possible
- • Use usage-based pricing for infrastructure (AWS, not reserved instances)
- • Implement hiring freeze, rely on current team
Example: SaaS company burning $200K/month cuts $40K (20%) by pausing Facebook ads (poor CAC), switching from Salesforce to HubSpot ($15K/year savings), and freezing 2 planned hires. Revenue growth slows from 15% to 12% monthly, but runway extends from 8 months to 12 months—buying critical time to achieve profitability or raise capital.
When should I start fundraising based on runway?
Start fundraising when you have 12-18 months of runway remaining. Here's why:
Typical Fundraising Timeline (6-9 months):
- • Months 1-2: Prepare deck, financial model, investor list (while you still have 12+ months runway)
- • Months 3-5: First meetings, due diligence, term sheet negotiations
- • Months 6-8: Legal docs, final diligence, wire transfer
- • Month 9: Buffer for delays (investors back out, due diligence issues)
If you wait until <6 months runway, investors smell desperation and offer terrible terms (2x liquidation preference, heavy ratchets, board control). You also lack negotiating leverage—you MUST take any deal to survive.
Pro tip: Always be in "fundraising mode" with 18+ months runway. Have regular investor updates, quarterly coffee meetings, warm intros. When you need capital, you're activating a warm network, not cold emailing strangers. This can compress fundraising from 9 months to 3-4 months.
What's the difference between gross burn and net burn?
Gross Burn Rate is your total monthly cash outflow—all expenses regardless of revenue. It includes salaries, rent, marketing, software, everything. Formula: (Starting Cash - Ending Cash) / Months.
Net Burn Rate is cash outflow minus revenue—the actual rate at which you're depleting reserves. Formula: Gross Burn - Monthly Revenue.
Example Comparison:
Company with $100K gross burn, $30K monthly revenue:
- • Gross Burn: $100K/month (how much you spend)
- • Net Burn: $70K/month (how much cash you lose)
- • Current Cash: $350K
- • Gross Runway: $350K ÷ $100K = 3.5 months (if revenue disappeared)
- • Net Runway: $350K ÷ $70K = 5 months (realistic runway)
Always use net runway for planning—it's your true survival timeline. However, monitor gross burn for worst-case scenarios (what if revenue drops 50%?). Conservative founders plan for net runway but keep emergency reserves based on gross burn calculations.
Can a company have negative burn rate (be profitable)?
Yes! When monthly revenue exceeds monthly expenses, your net burn rate becomes negative—meaning you're generating cash, not burning it. This is profitability (on a cash basis).
Profitability Stages:
- • High Net Burn ($50K+/month): Early-stage, pre-product-market fit, investing heavily in growth
- • Moderate Net Burn ($10-50K/month): Growing revenue but still burning cash, approaching breakeven
- • Near Breakeven ($0-10K/month): Revenue almost covers expenses, 1-2 months from profitability
- • Profitable (negative burn): Revenue > expenses, generating $10K+/month cash, can self-fund growth
- • Highly Profitable (strong negative burn): Generating $100K+/month cash, optionality to reinvest or save
Strategic Note: Some profitable companies choose to "burn cash" by intentionally spending more than revenue to accelerate growth. Example: Mailchimp was profitable at $5M revenue but could have raised VC, burned $10M/year, and grown faster. They chose bootstrapped profitability and sold for $12B in 2021. Both paths work—depends on market timing, competition, and founder goals.
How does burn rate affect company valuation?
Burn rate directly impacts valuation through the burn multiple metric that investors use to assess capital efficiency:
Burn Multiple Benchmarks (for SaaS companies):
- • <1.0x: Exceptional efficiency, can command premium valuations (15-20x ARR)
- • 1.0-1.5x: Good efficiency, typical for best-in-class startups (10-15x ARR)
- • 1.5-2.5x: Acceptable, market-rate valuations (8-12x ARR)
- • 2.5-4.0x: Inefficient, depressed valuations (5-8x ARR) and harder fundraising
- • >4.0x: Highly inefficient, investors pass or demand heavy discounts (3-5x ARR)
Example: Two companies, both at $2M ARR:
- • Company A: $150K net burn, adding $150K ARR/month → Burn multiple = 1.0x → Valued at $30M (15x ARR)
- • Company B: $500K net burn, adding $100K ARR/month → Burn multiple = 5.0x → Valued at $10M (5x ARR)
Company A raises at 3x higher valuation despite identical revenue because it's capital efficient. Lower burn means less dilution needed to reach profitability, higher investor returns, and premium valuations. In 2023's market, burn multiple became more important than growth rate for valuations—profitable growth beats high-burn hyper-growth.