ROI is a deceptively simple metric — and most calculators get it wrong by ignoring the time dimension. This one shows both: the raw percentage gain on the original cost, and the CAGR-equivalent annualised return when you supply a holding period in years.
The numbers are rendered in green for a positive return and red for a loss, with the absolute net gain shown alongside the percentage so you can't accidentally celebrate a "100% return" that's only $50. Nothing is stored — refresh the page and the inputs reset.
Simple ROI: (Final value − Initial investment) ÷ Initial investment, expressed as a percentage. It does not factor in additional contributions, withdrawals or transaction costs — for that, use a TWRR or IRR calculator.
It uses the compound annual growth rate (CAGR) formula: (Final ÷ Initial)^(1 ÷ Years) − 1. This tells you the equivalent steady annual return that would have produced the same end value over the same period.
Annualised return is per year, while simple ROI is the total over the whole holding period. A 35% gain over 3 years is roughly 10.5% per year compounded, not 11.7%, because of compounding.
No — it gives nominal pre-tax return. To get a real return, subtract the average annual inflation rate over the same period. To get an after-tax return, apply your local capital-gains rate to the gain.
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