Enter what you put in and what you got back to see your return on investment, and how much that is per year so you can compare investments held for different lengths of time.
The ROI formula
ROI = (amount returned − amount invested) ÷ amount invested × 100
ROI tells you the total gain, but not how long it took. A 50% return in 2 years is far better than 50% in 10 years. The annualized ROI is the steady yearly rate that would turn the same investment into the same result:
Annualized ROI = (amount returned ÷ amount invested)1 ÷ years − 1
Worked example
You invest $10,000 and get back $15,000. The gain is $5,000, so ROI = 5,000 ÷ 10,000 = 50%. Over 3 years, the annualized ROI is 1.51/3 − 1 = 14.47% a year. Over 5 years (January 1, 2020 to January 1, 2025) it's 1.51/5 − 1 = 8.45% a year.
When you enter dates, Calcist counts whole years between them, then adds the remaining days as a fraction of the next year. An investment made on February 29 reaches its anniversary on February 28 in years that aren't leap years.
Limitations
- Money added or taken out along the way. ROI only uses a start and an end. If you added money or received payments in between, use the IRR calculator, which accounts for timing.
- Costs. Include fees, commissions and taxes in the amounts so the ROI is what you really made.
- Risk. Two investments with the same ROI can carry very different risks.
- Short periods. Annualizing a few weeks or months magnifies the result. A 5% gain in one month annualizes to almost 80%, which says little about the future.
This is a planning estimate, not financial, tax or investment advice.
Sources
How we checked this
Before every update, this calculator is run in a real browser with these known answers, and it must match all of them:
- $10,000 to $15,000 is a $5,000 gain, 50% ROI ✓
- Over 3 years that's 14.47% a year ✓
- Jan 1, 2020 to Jan 1, 2025 (5 years): 8.45% a year ✓
- Feb 29, 2024 to Feb 28, 2025 is exactly 1 year: 50% a year ✓
- Getting nothing back is −100% ✓
Last checked October 26, 2026. Spotted something wrong? The math is done in your browser with the formula shown on this page, so you can check any result by hand.
Questions people ask
How do I calculate ROI?
Subtract what you invested from what you got back, divide by what you invested, and multiply by 100. $10,000 that becomes $12,500 is a 25% ROI.
What is annualized ROI?
The yearly rate that, compounded, gives the same total return. 50% over 3 years is 14.47% a year, not 16.67%, because each year's gain builds on the last.
What is a good ROI?
It depends on the risk and the time. Compare the annualized ROI with what a safe alternative, like a CD or Treasury, paid over the same years.
Can ROI be negative?
Yes. If you get back less than you invested, ROI is negative. Losing everything is −100%.
Is ROI the same as CAGR?
Annualized ROI and CAGR use the same math. CAGR is usually used for a value growing over time, like a fund or revenue; ROI for what an investment returned.