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Runway & Burn Rate

Translate current cash and monthly net burn into runway months and days. Add a burn increase per month to model acceleration.

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Runway & Burn Rate

Estimate cash runway with constant or increasing monthly burn.

Estimated runway
8.8 months (~265 days)

Runway math

When burn is constant, Runway = Cash ÷ Burn. When burn increases by Δ each month, the calculator solves the quadratic cash ≥ burn·n + ½Δ(n² − n).

How to use

  1. Enter cash on hand and current monthly net burn.
  2. Optionally add the amount burn grows each month.
  3. Review runway in months and days.

Example

Input: Cash = $750k, Burn = $85k/mo, Burn increase = $5k/mo

Output: Runway ≈ 8.3 months (~249 days)

Student-friendly breakdown

This walkthrough emphasizes the most searched ideas for Runway & Burn Rate: Runway & Burn Rate. Start with the formula above, then follow the guided steps to double-check your work. For quick revision, highlight the givens, plug into the equation, and finish by verifying your units.

Need more support? Use the links below to open the long-form guide, browse additional examples, or hop into adjacent calculators within the same topic — each one is a quick way to double-check your work or handle a related question without starting from scratch.

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Deep dive & study plan

Runway & Burn Rate: Cash runway calculator with optional monthly burn increases. It's built around runway, burn rate, cash, so you can go from a raw question to a checked answer without switching tools.

The math behind it: When burn is constant, Runway = Cash ÷ Burn. When burn increases by Δ each month, the calculator solves the quadratic cash ≥ burn·n + ½Δ(n² − n).

To use it well: (1) Enter cash on hand and current monthly net burn. (2) Optionally add the amount burn grows each month. (3) Review runway in months and days. Keep your units consistent as you go, and re-run a case you already know the answer to — it's the fastest way to catch a typo before it throws off a result you're relying on.

Worked example: entering Cash = $750k, Burn = $85k/mo, Burn increase = $5k/mo returns Runway ≈ 8.3 months (~249 days). Try swapping in your own numbers next, especially a case you're unsure about, before you use this for something that matters.

Quick retention checklist

  • Speak the formula aloud (or annotate it) so the relationships stick.
  • Write each step in your own words and compare with the numbered list above.
  • Swap in new numbers for the Example to make sure the calculator (and your logic) handles edge cases.
  • Check at least one related calculator below — it's the fastest way to confirm your numbers still line up from a different angle.

FAQ & notes

Can I model declining burn?

Set the burn increase to zero and manually adjust burn downward each time you revisit the calculator.

Does it include new funding?

No. Add funding rounds to cash on hand when they close, then rerun the numbers.

What formula does the Runway & Burn Rate use?

When burn is constant, Runway = Cash ÷ Burn. When burn increases by Δ each month, the calculator solves the quadratic cash ≥ burn·n + ½Δ(n² − n).

How do I use the Runway & Burn Rate?

Enter cash on hand and current monthly net burn. Optionally add the amount burn grows each month. Review runway in months and days.