How to Use This Tool
Follow these steps to calculate your business’s burn rate and runway:
- Enter your current total cash reserves in the Cash Reserves field. This includes all liquid business funds available for operations.
- Add any monthly recurring funding (e.g., regular investor tranches, subscription revenue) in the optional Monthly Recurring Funding field. Leave as 0 if none applies.
- Select your preferred burn rate calculation method: Net Burn (accounts for revenue) or Gross Burn (total expenses only).
- Enter your total monthly operating expenses, including payroll, rent, software subscriptions, and other recurring costs.
- If using Net Burn, enter your average monthly revenue. This field is optional for Gross Burn calculations.
- Click the Calculate Runway button to view your detailed cash flow metrics. Use the Reset button to clear all fields and start over.
- Use the Copy Results button to save your metrics to your clipboard for reporting or planning.
Formula and Logic
This calculator uses standard startup and small business cash flow formulas:
- Gross Burn: Total monthly operating expenses, regardless of revenue. This is the total cash your business spends each month to operate.
- Net Burn: Gross Burn minus monthly revenue. This represents the actual cash your business loses (or gains) each month.
- Adjusted Burn: Net Burn minus monthly recurring funding. This accounts for regular cash inflows that offset your burn rate.
- Runway (Months): Cash Reserves divided by Adjusted Burn. This is how long your business can operate before depleting current cash reserves.
- Break-Even Revenue: Total monthly operating expenses. This is the revenue threshold you need to hit to eliminate net burn entirely.
All calculations assume static monthly expenses, revenue, and funding. For businesses with variable cash flows, use average 3-month rolling figures for more accurate results.
Practical Notes
These business-specific tips will help you interpret and apply your results effectively:
- Most early-stage startups aim for 6–18 months of runway to secure additional funding or reach profitability. E-commerce businesses with seasonal revenue should calculate runway using off-peak expense and revenue figures.
- Net burn is more useful for revenue-generating businesses, while gross burn is standard for pre-revenue startups. Traders and e-commerce sellers should use net burn to account for inventory costs and sales revenue.
- If your adjusted burn is negative (cash flow positive), you can reinvest surplus cash into growth initiatives instead of preserving runway.
- Recurring funding includes regular investor payments, subscription revenue, or retainer income. One-time funding injections should be added to your cash reserves total instead.
- Runway calculations do not account for unexpected expenses (e.g., equipment repairs, inventory write-downs). Add a 10–15% buffer to your expense total for more conservative planning.
Why This Tool Is Useful
Small business owners, entrepreneurs, and e-commerce sellers use burn rate calculations to make critical operational decisions:
- Determine when to raise additional funding or cut operating costs to extend runway.
- Set realistic revenue targets to reach break-even and profitability.
- Evaluate the impact of new expenses (e.g., hiring, expanding inventory) on cash reserves.
- Report cash flow metrics to investors, partners, or stakeholders during planning meetings.
- Avoid cash flow crises by identifying runway shortfalls early.
Frequently Asked Questions
What is the difference between gross burn and net burn?
Gross burn is your total monthly operating expenses, including all costs to run your business. Net burn subtracts your monthly revenue from gross burn, showing your actual monthly cash loss or gain. Use gross burn for pre-revenue businesses, and net burn for businesses with consistent revenue.
How much runway should my business have?
Most small businesses and startups aim for 6–18 months of runway. E-commerce sellers with seasonal sales may need 12–24 months of runway to cover off-peak periods. Businesses with predictable recurring revenue can operate with shorter runway (3–6 months) if they are cash flow positive.
Can I use this calculator for my e-commerce store?
Yes, this tool is tailored for e-commerce sellers. Enter your inventory costs, shipping expenses, and platform fees as part of your monthly operating expenses, and include your average monthly sales revenue to calculate net burn accurately.
Additional Guidance
For more accurate results, use 3-month rolling averages for expenses, revenue, and funding instead of one-time figures. If your business has variable costs, calculate best-case (low expenses, high revenue) and worst-case (high expenses, low revenue) scenarios to plan for uncertainty.
Regularly update your burn rate calculations (monthly or quarterly) to reflect changes in your business operations. Pair this tool with a cash flow statement to get a full picture of your business’s financial health.
Note that this calculator provides estimates only and does not account for taxes, one-time expenses, or changes in market conditions. Consult a financial professional for personalized business advice.