Formula
Runway formula
Runway = cash balance / (monthly expenses - monthly revenue)If monthly revenue is greater than expenses, the business is default alive at the current run rate.
Business Calculators
Cash Runway Calculator
Use this cash runway calculator to estimate how long current cash will last at a given monthly burn rate.
Reviewed May 25, 2026EstimateFormula shown
Live calculator
Cash runway
Runway9.4 months
Months before cash reaches zero at this burn rate.
Net burn$80,000
Cash consumed each month.
Monthly position-$80,000
Adjusted expenses: $145,000.
How to use
Steps
- Enter the current cash balance.
- Enter average monthly revenue.
- Enter average monthly expenses.
- Adjust expenses up or down if you expect burn to change.
Example
Sample calculation
Cash balance$750,000
Monthly revenue$100,000
Monthly expenses$145,000
Runway16.7 months
Calculator use
Best for
- Quick months of runway from cash balance, monthly revenue and monthly expenses.
- Pricing, runway, cash flow, or work assumptions before an operating decision.
- Base, conservative, and optimistic cases with visible inputs.
- Calculator math that can be shared with a teammate, client, or advisor.
Before relying on it
Check first
- Entering cash balance, monthly revenue and monthly expenses from different time periods or scenarios.
- Mixing cash and accounting profit, or monthly recurring items and one-time items.
- Leaving out taxes, payment fees, refunds, churn, seasonality, or delayed collections.
- Using one optimistic scenario without checking a conservative scenario too.
Benchmarks
How to read the result
The calculator is a decision aid, not a fixed rule. Use the output to compare scenarios and document your assumptions.
0 - 6 monthsTight
Usually requires immediate fundraising, cuts, or revenue acceleration.
6 - 12 monthsWatch
Enough to operate, but decisions should be made before the window closes.
12 - 18 monthsHealthy
Often gives a team time to improve metrics before raising or scaling.
18+ monthsFlexible
Creates room for strategy, experiments, and cleaner fundraising timing.
Calculator accuracy
Methodology and assumptions
The formula, inputs, example, and limitations are shown so the result is checkable, not just a number in a box.
Formula
Runway = cash balance / (monthly expenses - monthly revenue)
Inputs used
Cash balance, Monthly revenue, Monthly expenses, Burn change
Limitations
Results are estimates for quick planning and should be checked before important financial, legal, tax, health, or business decisions.
Last reviewed
May 25, 2026
Cite this page
Toolkit Shelf. Cash Runway Calculator. Retrieved May 25, 2026, from https://toolkitshelf.com/tools/startup-runway-calculator
FAQ
Common questions
What is cash runway?
Cash runway is the number of months a business can keep operating before cash reaches zero at the current or projected burn rate.
What is net burn?
Net burn is monthly expenses minus monthly revenue. If revenue is greater than expenses, the business is not burning cash.
How often should runway be recalculated?
Most teams should recalculate runway monthly, and again after major hiring, pricing, or revenue changes.