Cash Flow Forecast Calculator

How to Use This Cash Flow Forecast Calculator

• Starting Cash — your current bank balance.
• Monthly Revenue Growth — the rate your revenue grows each month (use 0 for flat).
• Inflows — monthly revenue and any other income.
• Outflows — payroll, rent, COGS, marketing, and other expenses.

The calculator projects your cash balance for 12 months, flags your lowest cash month, warns you if cash goes negative, and lets you export the whole forecast to CSV.

What Is a Cash Flow Forecast?

A cash flow forecast projects how much cash your business will have at each point in the future, based on expected money in and money out. Unlike a profit-and-loss statement, which can show a profit while your bank account runs dry, a cash flow forecast tracks actual cash — the thing that keeps the lights on, makes payroll, and pays suppliers.

Cash flow is the number one reason small businesses fail — not lack of profit, but running out of cash at the wrong moment. A forecast is how you see that moment coming. By projecting 12 months out and spotting your lowest cash point, you can act early: line up financing, accelerate collections, delay a hire, or cut spend — long before it becomes a crisis. The same logic powers the 13-week cash flow forecast that finance teams use for tighter, near-term control.

Cash Flow Formula

Each month\'s ending cash becomes the next month\'s starting cash — which is why a small monthly shortfall compounds into a serious problem over a few months if left unaddressed.

Example Calculation

Starting cash $50,000; revenue $40,000 growing 3%/month; outflows of $43,000/month (payroll, rent, COGS, marketing, other):

• Month 1 net = $40,000 − $43,000 = −$3,000 → cash falls to $47,000
• As revenue compounds at 3%, the monthly gap narrows and eventually turns positive
• The calculator shows the exact month your cash bottoms out before recovering

Common Mistakes to Avoid

• Forecasting profit instead of cash. Profit and cash are not the same; forecast the cash.
• Forgetting timing. Revenue you have earned but not collected does not pay this month\'s bills.
• Leaving out lumpy costs. Quarterly taxes, annual renewals, and one-time purchases wreck a too-smooth forecast.
• Being too optimistic on revenue. Forecast conservatively; hope is not a cash flow strategy.
• Forecasting once and forgetting. A forecast is a living tool — update it as actuals come in.

Cash Flow Forecasting for Small Business & Startups

Cash flow forecasting is the single most valuable financial habit a small business can build, and it is the core of what a fractional CFO does day to day. A good forecast does not just predict — it lets you run scenarios: what happens to cash if we hire, if a big client pays late, if revenue grows slower than hoped. That foresight is the difference between managing your business and being managed by it.

This calculator gives you a solid 12-month view. For tighter control, our team builds rolling 13-week and 12-month cash flow models tied to your real numbers, with scenario planning built in. If cash flow keeps you up at night, that is exactly the problem we solve — let\'s talk.

Frequently Asked Questions

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