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Business Runway Calculator

See how many months your business can operate at the current burn rate — a stress-test for pricing, spending, and cash reserves.

Enter every amount in the same currency. This selector only changes the symbol shown — it does not convert exchange rates.

Cash & buffer

Cash you refuse to spend.

Monthly numbers

Monthly income

$1,800.00

Monthly expenses

$2,100.00

Monthly net

−$300.00

Monthly burn

$300.00

Usable cash

$9,000.00

After buffer

Months of runway

30.0

Runway is 30.0 months. Healthier — but keep watching monthly burn.

All calculations are estimates based on average platform fees. Real profits may vary depending on category, ads, and shipping.

Free worksheet for your next step

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How to use this calculator

  1. Enter your numbers in each field above — the calculator updates instantly as you type, so there's nothing to submit.
  2. Use your real figures when you have them, or sensible estimates while you're planning. If a field doesn't apply, leave it at zero.
  3. Compare the results, then change one input at a time to see how each lever (price, cost, fees, volume) moves the outcome.

Formula

Burn = max(Expenses − Revenue, 0) · Usable cash = Cash − Buffer · Runway (months) = Usable cash ÷ Burn

Worked example

$10,000 cash, $1,000 buffer, $2,100 monthly expenses, $1,800 revenue.

  1. Burn = 2100 − 1800 = $300
  2. Usable = 10000 − 1000 = $9,000
  3. Runway = 9000 ÷ 300 = 30 months

Answer: ≈ 30 months of runway

How it works

Runway is a wake-up call — under six months and every decision changes. If revenue covers expenses, runway is effectively infinite; the calculator shows that too.

How to interpret your results

  • Dollar values are shown per sale, per order, or per item unless a result is explicitly labelled monthly, weekly, or daily.
  • Percentages (margin, ROI, conversion rate) are easier to compare across products and price points than raw dollars — use them when you benchmark.
  • A positive result means you're ahead after the costs and fees you entered. A negative result means the current numbers don't work — change a lever (raise price, cut a cost, lower ad spend) and recalculate.
  • Treat the output as a planning estimate, not a guarantee. Fees, taxes, and conversion rates shift over time — re-run the numbers whenever a key input changes.

Common mistakes

  • Excluding owner draw from expenses.
  • Using best-month revenue instead of a realistic average.
  • Treating emergency buffer as spendable cash.

Go deeper with plain-English guides on the same topic.

FAQ

What's a healthy runway?
6–12 months is comfortable for most solo businesses. Under 3 months is a red alert.
Does runway assume revenue stays flat?
Yes — it's a snapshot at current numbers. Rerun it after any big change.

Why trust this calculator?

This tool uses standard mathematical formulas and commonly accepted calculation methods, shown openly in the Formula section above so you can verify the math yourself. Results are estimates based on the information you enter and do not account for every individual circumstance. For important financial, tax, legal, medical, or business decisions, please double-check with a qualified professional before acting on the numbers.

Keep going

One calculator rarely tells the full story. Pair this one with a related tool below to pressure-test your numbers from a different angle, or browse Selling & Business Calculators for more in the same category.

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