Cash Flow Calculator
Project your cash balance over time
Cash Flow Management for Small Business
Cash flow is the lifeblood of any business. 82% of small businesses fail due to cash flow problems. This calculator helps you project your cash position and identify potential shortfalls before they happen.
13-Week Cash Flow Forecast
The 13-week (quarterly) cash flow forecast is the gold standard for small business financial planning. It provides enough detail to spot short-term cash crunches while remaining simple enough to update weekly.
Written by Finance Experts · Last updated September 2026
Frequently Asked Questions
What is a good cash runway?
Most financial advisors recommend maintaining 3-6 months of operating expenses as cash reserves. Startups should aim for 12-18 months. If your runway is below 3 months, focus on reducing expenses or accelerating revenue immediately.
How do I improve cash flow quickly?
Quick wins: (1) Invoice immediately and follow up on late payments, (2) Negotiate longer payment terms with suppliers, (3) Offer discounts for early payment, (4) Cut non-essential expenses, (5) Consider a business line of credit for short-term gaps.
What is the difference between cash flow and profit?
Profit is revenue minus expenses on paper. Cash flow is the actual movement of money in and out of your account. A business can be profitable but cash-flow negative if customers haven't paid yet, or if large expenses are due before revenue arrives.
When should I worry about cash flow?
Warning signs: (1) Cash runway below 3 months, (2) Consistently negative monthly cash flow, (3) Delayed customer payments becoming a pattern, (4) Relying on credit cards or loans to cover operating expenses, (5) Can't take advantage of growth opportunities due to cash constraints.
How often should I update my cash flow forecast?
Weekly for businesses with tight cash flow, monthly for stable businesses. Update whenever you receive large invoices, make significant purchases, or experience changes in revenue. The 13-week forecast should be reviewed and adjusted every week.
What is operating cash flow?
Operating cash flow is the cash generated from your core business operations, excluding investment and financing activities. It shows whether your business model is sustainable. Positive operating cash flow means your day-to-day business generates more cash than it consumes.
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Data Sources & Citations
- OfficialInternal Revenue Service (IRS)
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