Return on Investment (ROI)

Return on investment (ROI) is a ratio that measures how much an investment gained or lost compared with what it cost, usually expressed as a percentage. Investors use it to judge a share, a property or a crypto position; managers use it to compare projects such as a marketing campaign, a new machine or a software system. Its appeal is simplicity: one number answers the question "for every dollar put in, how much came back?"

ROI is a general-purpose measure rather than a formally standardised one, so companies and analysts define "gain" and "cost" in different ways. It is closely related to, but distinct from, measures that account for time, such as the Compound Annual Growth Rate (CAGR) and Annual Percentage Yield (APY), and from measures of income such as Yield. Read on its own, ROI says nothing about how long the money was tied up or how much risk was taken.

Suppose you buy a used bicycle for 100, spend 20 fixing it up, and sell it for 150. You put in 120 and got back 150, so you are 30 better off. Compared with the 120 you spent, that 30 is a quarter, so your return on the investment is 25%.

That is all ROI does: it compares what you made with what you spent. It is handy for comparing very different choices, such as fixing bicycles versus selling lemonade. But it does not tell you whether the bicycle took a week or two years to sell, or how likely you were to lose money along the way.

The standard calculation is:

• Final value is what the investment is worth at the end, including income received, such as dividends, Interest or staking rewards.
• Cost of investment is everything paid to acquire and hold it, including purchase price and fees.
• Multiplying by 100 turns the ratio into a percentage.

Worked example in crypto: suppose an investor buys a token for $10,000, pays $50 in exchange fees and a $10 network Gas Fee to move it to a wallet, earns $300 of rewards from Staking, and later sells for $11,500 after paying another $50 fee. The total cost is $10{,}000 + 50 + 10 = 10{,}060$. The final value is $11{,}500 - 50 + 300 = 11{,}750$. So:

The return is about 16.8%. Ignoring the fees and rewards would have given 15%, which shows why each Transaction Fee belongs in the cost.

Because plain ROI ignores time, investors often convert it to a yearly rate:

where $n$ is the number of years the money was invested; multiply the result by 100 for a percentage. A 50% ROI earned over four years gives $1.5^{1/4} - 1 \approx 0.107$, about 10.7% a year, the same idea as CAGR. A 16.8% ROI earned in six months is far more impressive than the same figure earned over five years. For short periods within a calendar year, results are often reported as Year to Date (YTD) returns instead.

• Investing. Investors compare ROI across holdings in a Portfolio, and against a benchmark such as the Risk-Free Rate on Treasury Bills (TBs); a return below that rate means the risk was not rewarded.
• Crypto. Traders quote ROI on positions, on Yield Farming strategies and on mining equipment. Positions using Leverage magnify ROI on the investor's own capital in both directions.
• Business. Companies estimate ROI before spending on a project, and marketing teams compare campaign revenue with spend, alongside measures such as Customer Acquisition Cost (CAC).
• Venture investing. Funds in Venture Capital often prefer multiples (for example "3x") and internal rate of return, because cash goes in and comes out at different times.

• Time. Without annualising, ROI cannot compare investments held for different periods.
• Risk. Two investments with equal ROI may carry very different risk; ROI should be read alongside the investor's Risk Tolerance and measures of volatility.
• Inflation. A nominal ROI of 5% during 6% Inflation is a loss of purchasing power.
• Taxes. Pre-tax and after-tax ROI can differ widely, since gains on sale are often subject to Taxes.
• Cash-flow timing. When money is added or withdrawn over time, simple ROI can mislead; time-weighted returns or internal rate of return, which uses a Discount Rate on each cash flow, are more accurate.
• Paper versus realised gains. A rising price produces an unrealised ROI that can disappear before sale, as many holders who chose to HODL through a market top found when prices later fell from their All Time High (ATH).

• Investor.gov (SEC): Compound Interest Calculator