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ROI Calculator

Calculate ROI and annualized return for any investment.

Educational estimate. Past performance does not guarantee future results. Not investment advice.

Runs in your browserNo account requiredNo uploadFree
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About ROI Calculator

ROI Calculator works out the return on an investment as both a total percentage and an annualized rate. It is the right tool whenever you want a single number that says how well a one-shot investment performed — a project, an asset bought and sold, a marketing campaign — and an apples-to-apples comparison across investments held for different lengths of time.

Worked example: invest $10,000, sell three years later for $13,500. Total ROI is (13,500 − 10,000) / 10,000 = 35%. But over three years the annualized return is closer to 10.5% per year — ((1 + 0.35)^(1/3) − 1), the constant yearly rate that would produce the same total result. That is the figure you would compare against a savings account or an index fund quoted in annual terms.

Two things are worth understanding. Total ROI ignores time, so a 35% return looks identical whether it took one year or ten — that is why annualized ROI exists, and why both figures are usually quoted together. And ROI says nothing about risk: a guaranteed 5% and a coin-flip 5% are not the same investment, even when the headline number matches. The calculator also assumes a single inflow and a single outflow; if money was added or withdrawn in between, you want Internal Rate of Return (IRR) instead.

All math runs in your browser. Nothing about your investments is logged or uploaded.

Frequently asked questions

The constant yearly return that would produce the same total result over the holding period. It is what lets you compare investments held for different lengths of time on the same footing.

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