ROI Calculator
Calculate return on investment as a percentage and annualized rate from your initial cost and final value, free in your browser.
Enter Values
Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.
How to use this calculator
- Enter the amount invested and amount returned.
- Press Calculate.
How it works
ROI = (returned − invested) ÷ invested × 100 — the percentage gain or loss.
Worked example
$1,000 → $1,500. = 50% ROI, $500 profit.
Common mistakes
- Dividing by the amount returned instead of the amount invested.
- Ignoring fees, tax and how long the money was invested — ROI alone doesn't annualise.
Frequently asked questions
Is a higher ROI always better?
Not necessarily — a high ROI over 10 years can be worse than a smaller one over 1 year. Compare the time periods too.
How is ROI different from profit?
Profit is the dollar gain; ROI expresses that gain as a percentage of what you put in.
Does ROI account for time?
No — it's a simple percentage gain regardless of how long it took. For time-based comparison use payback period or an annualised return.
Related tools
- Payback Period Calculator
- Compound Interest Calculator
- Profit and Loss Percentage Calculator
- Profit Margin Calculator
- Gross Profit Calculator
- Break-Even Calculator
Explore more in Finance, Business, Property & Pricing.
Cite this tool
Zerdly. (2026). ROI Calculator. Retrieved from https://www.zerdly.com/tools/roi-calculator/
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.