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Max Monthly Spend for Your Runway

With $100,000 in cash and no income, you can spend about $5,556 a month and last exactly 18 months. If you also bring in $2,000 a month, your max spend rises to about $7,556. The simulator charts the cash balance draining to zero right at your target month.

Results

Visualization

BizTool provides illustrative business estimates only. Results depend on your inputs and assumptions and are not accounting, tax, or legal advice. Consult a CPA or financial advisor before major decisions.

How It Works

Total money available over the runway is cash plus income earned during those months. Dividing by the number of months gives the maximum you can spend each month. The monthly change is income minus max spend, which equals cash divided by months but negative, so the balance hits zero exactly at the target month.

What Should You Do?

Build in a buffer. Plan to run out a month or two later than your real deadline so an unexpected slow quarter does not sink you. If income is uncertain, model the zero-income case to know your true floor.

Frequently Asked Questions

Should I include expected income?

Only if it is reliable. If income is speculative, use 0 to find your worst-case burn and avoid overspending.

What if I want a cushion?

Add a few months to the runway input. The max spend drops, giving you slack if revenue slips.

Does this account for one-time costs?

No. One-time hits (equipment, legal) should be subtracted from cash first or modeled separately.

How is this different from a burn rate?

Burn rate is usually monthly net cash out. This reverses it: given a cash pile and a deadline, what burn can you afford.