ROI Calculator
Calculate return on investment as a percentage, plus annualised return over a holding period.
Processing: This tool runs entirely in your browser. Your input and any file you open stay on your device — nothing is uploaded to a server.
How to use the roi calculator
- Fill in the fields — they start with a worked example.
- Read the answer, and the arithmetic shown beneath it.
- Copy the results, or adjust the inputs to compare scenarios.
About this tool
Return on investment is profit divided by cost: (gain − cost) ÷ cost. It is the standard way to compare outcomes of different sizes, because it strips out the absolute amounts.
What plain ROI ignores is time. Doubling your money is impressive in a year and unremarkable over twenty, so the annualised figure is shown alongside — that is the compound rate which would produce the same result over the period you held it.
Common uses
- Comparing the return on two investments of different sizes.
- Reporting the outcome of a marketing spend.
- Checking whether a long hold actually beat a savings account.
Frequently asked questions
- What is a good ROI?
- It depends entirely on the risk and the time. A 10% return over a decade is poor; the same over a month is exceptional. Use the annualised figure to compare fairly.
- How is ROAS different?
- Return on ad spend is usually revenue divided by spend, not profit divided by spend — so a ROAS of 1 means you broke even on revenue, and probably lost money.
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