ROI Calculator – Technical & User Documentation

What It Does

A financial tool called the ROI Calculator assesses the profitability of a project, advertising campaign, or new product introduction. It creates a comprehensive picture of financial return by modeling monthly cash flows over a user-specified time period and applying compound revenue growth, operating costs, taxation, and discounting.

How to Make Use of It

1. Using the tabs at the top, choose the type of scenario (Project, Marketing Campaign, Product Launch). The basic model remains unchanged, but the context is labeled.
2. Fill in the left panel with your cost information:
   • Initial Investment: the initial investment made up front
   • Monthly Operating Cost: monthly recurring fixed expenses
   • Duration: total months spent modeling (1–60)
   • Discount Rate: the annual rate (e.g., 8% for a standard cost of capital) used to determine net present value (NPV)
3. Fill in the panel on the right with your revenue data:
   • Expected Monthly Revenue: the first month’s baseline revenue
   • Monthly Growth Rate: compound growth applied every month after that
   • Salvage Value: the remaining asset value recovered at the conclusion of the term

Only positive net cash flows are subject to the tax rate. Every time an input is changed, all results are instantly updated.

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Formulas Used

Monthly Revenue (compounded growth)

Revenue(m) = Revenue(1) × (1 + g)^(m−1)

where g is the monthly growth rate and m is the month number.

Monthly Net Cash Flow (before tax)

NetCash(m) = Revenue(m) − OperatingCost

Tax (applied only when net cash is positive)

Tax(m) = NetCash(m) × TaxRate,  if NetCash(m) > 0
Tax(m) = 0,                      otherwise

After-Tax Cash Flow

AfterTax(m) = NetCash(m) − Tax(m)

Cumulative Net Position

CumNet(m) = −InitialInvestment + Σ AfterTax(i),  i = 1…m

Salvage value is added to AfterTax in the final month.

Total Cost

TotalCost = InitialInvestment + (OperatingCost × Duration)

ROI

ROI (%) = (CumNet(final) / TotalCost) × 100

Net Present Value (NPV)

Monthly discount rate: r = AnnualRate / 12

NPV = −InitialInvestment + Σ [ AfterTax(m) / (1 + r)^m ],  m = 1…Duration

A positive NPV means the investment creates value above the required rate of return. A negative NPV means it does not.

Break-Even Month

BE = first m where CumNet(m) ≥ 0

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Reading the Output

Metric	Meaning
ROI %	Total net return as a percentage of total capital invested
Net Profit	Absolute profit after all costs and taxes
NPV	Present value of all future cash flows minus initial investment
Total Revenue	Gross cumulative revenue over the full period
Total Cost	All cash out: upfront + operating (tax excluded)
Break-Even	Month when the project first recovers its full investment

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Interpreting the Charts

Monthly Cash Flow

Bars display monthly revenue, while the green line shows net cash after taxes, indicating the point at which monthly operations turn a profit.

Cumulative Investment vs. Returns

The green line represents the net position, the amber region represents cumulative revenue, and the red area represents total capital deployed. The break-even point occurs where the green line crosses zero.

Cost Breakdown

A proportionate distribution of the initial investment, all operating expenses, and all taxes paid.

Projection Table

A quarterly (for longer periods) or monthly (for durations ≤ 24 months) analysis of all metrics with running ROI.

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Exporting

Each section of a PDF report—including the header, inputs, results, charts, and table—is produced as a separate image and arranged sequentially within an A4 document. Pages never break inside a chart or card; they only break between sections.

Share Link

Every input value is encoded as a URL parameter. The exact scenario is restored when the link is opened.