ROI Formula

Every investment decision comes down to one question: how much profit will this generate compared to what it costs? The ROI formula answers that question in a single percentage.

What Is the ROI Formula?

Basic ROI formula:

ROI = (Net Return ÷ Cost of Investment) × 100%

where Net Return = Final Value of Investment – Cost of Investment.

In other words:

ROI = ((Gain from Investment – Cost of Investment) ÷ Cost of Investment) × 100%

This universal formula works for stocks, real estate, business projects, and even marketing campaigns. You simply divide the net gain (or loss) by the amount you put in, then multiply by 100 to express it as a percentage.

An alternative version uses net profit directly:

ROI = (Net Profit ÷ Cost of Investment) × 100%

Both forms are equivalent as long as net profit equals the gain minus the initial cost.

How to Calculate ROI: Step by Step

Follow these steps with any investment:

1. Determine the total cost of investment – Include purchase price, fees, commissions, and any additional capital you added.
2. Identify the final value or total return – For a stock, it’s the sale price plus dividends received. For a project, it’s the extra profit generated.
3. Subtract cost from final value to get the net return (can be negative).
4. Divide the net return by the total cost.
5. Multiply the result by 100 to get the ROI percentage.

If your numbers are in different currencies or units, the formula still works – ROI is unitless.

Example Using the ROI Formula

Suppose you bought shares of a company for $5,000. After one year, the investment is worth $6,200, and you received no dividends.

• Cost of investment = $5,000
• Final value = $6,200
• Net return = $6,200 – $5,000 = $1,200
• ROI = ($1,200 ÷ $5,000) × 100% = 24%

Your return on investment is 24%.

Now consider a small business: you spend $50,000 on new machinery and it brings in an extra $18,000 profit over its useful life.

• Net return = $18,000 (extra profit) – $50,000 (cost) = –$32,000? Wait, that’s not right because the machinery has residual value or profit is above cost. Let’s clarify: if the machinery generates $68,000 in total additional revenue and costs $50,000, the net gain is $18,000. So ROI = (18,000 ÷ 50,000)×100 = 36%.

Use the calculator below to quickly run your own numbers.

Enter your initial outlay and the final value or net profit. If you know the holding period in years, the calculator also gives you the annualized ROI.

Annualized ROI Formula

Basic ROI doesn’t care about how long you held the investment. A 30% return over 5 years is very different from 30% in 6 months. To compare investments with different timelines, use the annualized ROI formula:

Annualized ROI = [ (Final Value ÷ Initial Investment)^(1 / n) – 1 ] × 100%

where n is the number of years.

Example: $10,000 grows to $16,105 over 5 years.

• (16,105 ÷ 10,000) = 1.6105
• Raise to the power of (1/5) = 0.2: 1.6105^0.2 ≈ 1.10
• Subtract 1 and multiply by 100: 10%

The annualized ROI is 10% per year.

For periods shorter than a year, use the fraction of a year (e.g., 0.5 years for 6 months) in the formula. Annualized ROI lets you compare a 2-year bond, a 5-year stock investment, and a 3-month marketing campaign on equal footing.

Interpreting ROI Results

• Positive ROI – You earned more than you invested. The higher the percentage, the more profitable the investment.
• 0% ROI – You broke even; final value equals cost.
• Negative ROI – A loss; the investment returned less than you put in.

There is no universal “good” ROI threshold because acceptable returns depend on risk, industry, and your alternatives. A 12% annualized ROI might be excellent for a low-risk bond but disappointing for a high-growth startup. Compare against industry benchmarks or your own required rate of return.

When Is ROI Most Useful?

ROI is widely used because it’s simple and adaptable:

• Stock and real estate investing – Quickly gauge how much a property or portfolio grew.
• Business projects – Compare expected returns of new equipment, software, or marketing pushes.
• Marketing – Calculate (Revenue from campaign – Cost) ÷ Cost × 100% to rank ad performance.
• Personal finance – Evaluate whether a side hustle, education, or major purchase pays off.

Because ROI translates any gain into a percentage, you can directly compare vastly different opportunities – just remember to use annualized ROI if time horizons differ.

Limitations of the ROI Formula

ROI has blind spots:

• Ignores time – Basic ROI makes a 1-year 20% gain look identical to a 5‑year 20% gain.
• Doesn’t factor in risk – Two investments with the same ROI can have very different risk profiles.
• Doesn’t account for cash flow timing – Money earned earlier is more valuable than later payments.
• Can be manipulated – Different definitions of “cost” and “return” (before or after taxes, inclusive of fees) can change the result.

For more complex decisions, consider supplemental metrics like Internal Rate of Return (IRR) or Net Present Value (NPV).

This content is for informational purposes only and does not constitute financial advice.