Cash Flow Calculator
Free cash flow calculator — see how many months your cash will last based on income and expenses. Get a 3–6 month business forecast instantly.
Disclaimer: This tool provides estimates for informational purposes only and does not constitute financial, tax, or legal advice. Results may vary based on your specific circumstances. Always consult a qualified professional before making financial decisions.
This cash flow calculator shows you how long your current cash balance will last based on your monthly income and expenses, and gives you a 3–6 month forecast so you can plan ahead. For small businesses and freelancers, understanding your cash flow runway is more immediately useful than knowing your profit — cash in the bank is what keeps operations running.
Enter your current cash balance, your expected monthly revenue, and your monthly fixed costs. The calculator determines your net monthly cash position (positive if revenue exceeds costs, negative if costs exceed revenue) and projects your balance forward month by month. If you are cash-flow negative, it shows when your balance hits zero so you know how much runway you have left to find new clients or cut costs.
A positive net cash position means you are growing your reserves each month. A negative position means you are drawing down — not necessarily a crisis if it is temporary, but something to track closely. The 3–6 month view makes seasonal patterns visible: a month with a big project landing followed by a slow stretch looks very different on a graph than in a snapshot.
The calculator is intentionally simple — single revenue and expense inputs — because the goal is a quick, honest picture of your financial situation, not a complex model. If you want more granularity, use the Monthly Budget Calculator to break expenses into categories, or track actuals in the Expense Tracker.
Use this calculator at the start of each quarter, when you lose or add a major client, or whenever your spending changes significantly. The output tells you whether your current financial plan is sustainable or whether you need to take action.
Frequently Asked Questions
- What is a cash flow runway calculator?
A cash flow runway calculator shows how many months your current cash will last based on your income and expenses. If your monthly expenses exceed monthly revenue, it calculates when your balance will hit zero — giving you time to take action before a cash crisis.
- Is there a free cash flow calculator for small businesses?
Yes. This cash flow calculator is completely free — no account, no signup. Enter your cash balance, monthly revenue, and monthly expenses to get an instant forecast. No download required.
- What is cash flow runway?
Cash flow runway is the number of months a business can continue operating at its current burn rate before running out of cash. It is calculated as current cash balance ÷ net monthly cash burn. A business with $30,000 cash burning $5,000/month net has 6 months of runway.
- What is a healthy cash flow runway for a small business?
Most financial advisors recommend 3–6 months of operating expenses as a cash reserve. Freelancers and project-based businesses often need more — 6–12 months — because income is irregular. The right number depends on how predictable your revenue is.
- How is this different from a profit calculator?
Profit is revenue minus costs on paper. Cash flow is actual money in versus actual money out. A business can be profitable on paper but cash-flow negative if clients pay late, you have upfront costs, or timing mismatches exist between revenue and expenses. This calculator focuses on cash — what is actually in your account.
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