ROI Calculator

Estimate investment growth, profit, ROI %, and CAGR. Add optional monthly contributions, annual fees, and an inflation-adjusted view. Educational estimates only — not financial advice.

Inputs

Use realistic assumptions. The biggest drivers are time, contributions, and return rate.

How this ROI calculator works

This ROI calculator estimates return on investment using profit, ROI %, and (when applicable) CAGR to compare opportunities across different time horizons. Enter your initial investment, final value (or profit), and the time period. ROI shows the total percentage gain; CAGR smooths returns into an annualized rate so you can compare investments with different durations. Use it for simple scenarios (projects, business spends, or investments). For investments with deposits/withdrawals over time, results may differ from true internal rate of return.

Practical tips: use net profit after costs for accuracy; use CAGR when comparing investments over different time periods; treat very high projected returns as higher risk and test downside cases. Limitations: results assume fixed rates and steady payments/contributions. If your situation changes (rate changes, fees, irregular income), rerun the calculator with updated inputs to keep your plan accurate.

If you’re comparing two projects, use the same timeframe and include all costs (setup, tools, transaction fees). That makes ROI comparisons fair and decision-ready.

Tip: Fees matter. A 1% annual fee can reduce long-term results more than most people expect.

Results

Updated when you click Calculate.

Ending value
Projected portfolio value at the end.
Profit (growth)
Ending value − total contributions.
ROI %
Profit ÷ total contributions.
CAGR
Annualized return (effective).
Enter your numbers and click Calculate.

How this calculator works

We simulate growth period-by-period (monthly/quarterly/annual), add contributions, then apply an annual fee approximation by reducing the gross return. Inflation (if provided) is used only to show a “today’s money” view of the ending value.

ROI is total profit as a percentage of what you put in. CAGR is the annualized rate that would turn your total contributions into the ending value over the same time.
We approximate fees by reducing your annual return by the fee %. This matches the typical “net return” approach for fund/ETF fee modeling.
No. Taxes depend on your country, account type (ISA, pension, brokerage), and holding period. Use this as a baseline scenario tool.

Calculator methodology & assumptions

This calculator uses standard financial formulas and simplified assumptions (for example: constant rates, regular payments, and rounding). Real-world results can differ due to fees, taxes, rate changes, compounding conventions, and account rules.

See how we build and validate our tools: Calculator Methodology. For how we review content: Editorial Policy.

Related calculators

Use these tools together to compare scenarios (fees, contributions, debt payoff, and retirement projections).

Frequently Asked Questions

What is ROI?

ROI (return on investment) measures profit relative to the cost of an investment. It helps compare opportunities on a consistent basis.

How is ROI calculated?

A simple ROI formula is (gain − cost) ÷ cost. Some ROI calculations also consider time and ongoing costs.

What’s the difference between ROI and annualised return?

ROI is total return over the period. Annualised return adjusts the result to a yearly rate so investments of different lengths can be compared.

Should I include fees and taxes?

For a realistic comparison, include known costs such as fees, commissions, and taxes where applicable.

Can ROI be negative?

Yes. If the investment loses value or costs exceed gains, ROI becomes negative.