Formula breakdown (cash flow, runway, and “break‑even”)

This calculator is intentionally simple (and therefore fast). It estimates monthly net cash flow from your inputs, then projects your cash balance across the chosen period. The sliders simulate three common real‑world distortions: late customer payments, seasonal demand dips, and gradual expense creep.

• Base inflows = Revenue collected (cash basis), per month.
• Seasonality reduces inflows by a percentage (e.g., 10% dip means multiply by 0.90).
• Collection delay shifts some of this month’s inflows to the next month. We approximate this by multiplying inflows by a “collection efficiency” factor: efficiency = 1 − delayDays / 90 (clamped so it never goes below 0.35).

• Total outflows = COGS + Operating Expenses + Debt Payments + Taxes + CapEx.
• Expense creep increases outflows by a percentage (e.g., 5% creep means multiply by 1.05).

• Net cash flow (monthly) = Adjusted inflows − Adjusted outflows.

• Ending cash = Starting Cash + (Net Cash Flow × Months).
• This is a straight‑line projection. Real cash balances fluctuate; this is designed to be a quick “is this direction safe?” check.

• If Net Cash Flow is negative (burn), then Runway (months) ≈ Starting Cash ÷ |Net Cash Flow|.
• If Net Cash Flow is positive, runway is “not applicable” — because you are not burning cash.

• Break‑even happens when Net Cash Flow = 0.
• We report how much you would need to change inflows (or reduce outflows) to reach 0, given your sliders.

Quick examples you can sanity‑check

• Starting cash: $10,000
• Revenue: $25,000
• COGS: $8,000, OpEx: $12,000, Debt: $1,000, Taxes: $1,500, CapEx: $500
• Sliders: 15 day delay, 5% seasonality dip, 3% expense creep
• You might be near break‑even. If collections slip to 45 days, net cash flow often flips negative — even though your “profit” story might sound fine.

• Starting cash: $60,000
• Net cash flow: −$6,000/month (burn)
• Runway ≈ 60,000 ÷ 6,000 = 10 months
• If you reduce burn to −$3,000/month, runway doubles to ~20 months. That’s why small operating changes can have huge strategic value.

• If your net cash flow is −$2,500/month, you can break even by either:
• Increasing inflows by ~$2,500/month, or reducing outflows by ~$2,500/month, or a combination.

Make it actionable in 10 minutes

The point of a cash flow model is not to be “correct.” It’s to help you choose the next move. Use this quick routine:

• Step 1: Enter your “typical month” numbers.
• Step 2: Slide collection delay to what actually happens (not what invoices say).
• Step 3: If net cash flow is negative, look at runway.
• Step 4: Pick one lever for the next 14 days: collections, margins, or expenses.
• Step 5: Recalculate weekly. Trends beat one‑time guesses.

• “What if my top client pays 30 days late?” (increase delay)
• “What if ads get 10% more expensive?” (increase expense creep)
• “What if sales dip 15% next month?” (increase seasonality dip)

Frequently Asked Questions

• Is this a full cash flow statement?

  No. It’s a simplified cash flow estimator meant for quick planning. A full statement separates operating, investing, and financing cash flows with accounting detail.

• Why do the sliders change the result?

  Because real‑world cash is mostly about timing and drift. Late payments reduce the cash you actually collect this month. Seasonality changes demand. Expense creep models the reality that costs tend to rise unless controlled.

• What should I put for “Revenue collected”?

  Use the amount of cash you typically receive in a month (bank deposits), not the amount you invoice. If you only know invoiced revenue, set a collection delay that matches your payment terms.

• What if I’m a freelancer or solo founder?

  It still applies. Treat payroll as part of OpEx (including your own pay). The best insight is often: “How many months can I keep running if clients pause?”

• Does “runway” include raising money?

  No. Runway assumes no new capital. If you plan to raise or take a loan, model that as additional starting cash (or as future inflows in a more advanced spreadsheet model).

• Can I save multiple scenarios?

  Yes — click Save. Your scenarios are stored locally in your browser (this device only).

Use this responsibly

This is a lightweight estimator meant for planning and learning. If you’re making major decisions (hiring, fundraising, loans), validate assumptions and timing with statements or a spreadsheet cash flow model.

• Model a “worst reasonable month” (higher delay, higher expense creep, higher seasonality dip).
• Identify your fastest cash lever (collections usually wins).
• Track weekly: net cash flow direction, not perfection.