Business calculator

Runway Calculator

Estimate how many months cash will last. Enter your values below to calculate in the browser and review the formula, example, and cautions on the same page.

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Runway Calculator

Enter the values you know. The result updates in your browser and stays separate from the notes and examples.

Use realistic values. Invalid, missing, or impossible inputs will show a friendly warning instead of a broken result.

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ResultEnter values, then calculate.Your output appears here after calculation.
Financial estimate: Estimate only. This result is for planning and reporting checks. It is not accounting, tax, legal, or financial advice. Match time periods and verify against your source records before making decisions.

Reviewed estimate context

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What this result is

Runway Calculator gives a browser-calculated estimate from the inputs you enter and the formula displayed on this page.

What can change it

Use the result to check a metric or scenario. Confirm final numbers against accounting records, analytics exports, invoices, tax rules, or professional guidance.

Formula transparency

Formula source type: standard business metric formula shown on this page. Last review marker: 2026-06-28. Report unclear formulas through the contact page.

Recent results on this device

Calculate once to save a local result on this device.

What is the Runway Calculator and Why Does It Matter?

The Runway Calculator estimates how many months cash will last. It divides cash by monthly burn.

Think of a toy rocket with limited fuel. Runway tells how long it can fly before fuel runs out.

A runway calculator helps teams plan before cash gets too low.

How the Math Works

runway = cash available ÷ monthly burn

SymbolMeaningSimple way to think about it
cash availableMoney on handFuel in the rocket
monthly burnCash used each monthFuel used each month
÷DivideSplit cash into months
runwayMonths leftHow long cash lasts

Example: $120,000 cash and $15,000 monthly burn.

  1. Start with $120,000.
  2. Divide by $15,000.
  3. $120,000 ÷ $15,000 = 8.
  4. Runway is 8 months.

Real-Life Examples

Example 1: Kid-friendly use

You have 24 game coins and spend 4 each day. You have 6 days left.

Example 2: Everyday adult use

A small business checks how long savings can cover monthly bills.

Mistakes to Avoid

Mistake 1: Using yearly spending instead of monthly burn.

Mistake 2: Entering zero burn. Cash cannot be divided by no monthly use.

Zero cash gives zero months. Negative cash means the business is already short.

Frequently Asked Questions

What happens if I enter zero?

Zero cash gives zero runway. Zero monthly burn is blocked because the result would not be useful.

Why is this easier than doing it by hand?

It quickly turns cash and burn into months. It also avoids unit mix-ups.

Can I use this with Burn Rate Calculator or Savings Goal Calculator?

Yes. Burn Rate Calculator finds monthly burn. Savings Goal Calculator plans a cash target.

FAQ

How should I use this result?

Use the result as a quick calculation, then review the formula, example, and related calculators if your situation needs a second check.

What if the result looks wrong?

Check the inputs, units, and formula. If a label or formula appears incorrect, contact CalculTools with the page URL and example values.

What should I check before using this result?

Check the input units, the formula shown on the page, and any assumption that does not match your situation.

What if the result looks off?

Recheck the values and units first. If the formula or label looks wrong, send the page URL and example values through the contact page.

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