ROI Calculator 🔒 Your data never leaves your browser.
Calculate return on investment as a percentage and net profit.
About this tool
This ROI calculator works out the return on investment percentage from two numbers: how much you put in (cost) and how much you got back (gain). The formula is simple — (gain − cost) ÷ cost × 100 — but doing it in your head under pressure is easy to get wrong, so the tool handles the arithmetic and shows both the percentage and the underlying net profit or loss. For example, invest $1,000 and sell for $1,500: that is a $500 profit on a $1,000 cost, or a 50% ROI.
One thing ROI on its own does not tell you is how long it took to earn that return. A 50% ROI earned in one month is a very different result from a 50% ROI earned over ten years — the first compounds into an enormous annual rate, the second barely beats inflation. Comparing returns across different time periods requires a separate metric, annualized ROI (or CAGR), which is not what this simple calculator computes; it only reports the total return over whatever period your numbers already cover.
Frequently asked questions
Does ROI account for how long the investment took?
No — this basic ROI calculation is time-agnostic: a 50% ROI made in one month and a 50% ROI made over ten years produce the exact same number here, even though the first is obviously a much better result. If you need to compare investments held for different lengths of time, look at annualized ROI (sometimes shown as CAGR), which spreads the return out per year — that's a different, more involved calculation not covered by this simple tool.