ROI Calculator

How to use the ROI calculator

1. For each investment, enter a Name, the Amount invested, the Final value and, if you know it, how long it was Held for (years). Decimals work: 1.5 means eighteen months.
2. Click Add an investment to compare up to eight investments; Remove deletes one.
3. Choose the Currency for display.

The results show the Total invested, the Total net profit, the Overall ROI of all the investments together and the Best investment. The Comparison table lists, for each investment, the net profit, the ROI and the Annualized ROI. Copy copies the table as text, and How it was calculated (first investment) details the formulas.

The ROI formula

Return on investment measures the gain or loss relative to the amount invested:

Net profit = final value − amount invested

ROI = net profit ÷ amount invested × 100

The final value should include everything you got back: the sale price plus the dividends, rent or interest received, minus the costs (commissions, fees, taxes paid on the transaction). Put any extra costs in the amount invested, for example the purchase price plus the closing costs.

Example: you invest $10,000 and get $14,000 back. The net profit is $4,000 and the ROI is 40%.

Annualized ROI: comparing investments fairly

A simple ROI ignores time. 40% in four years is not as good as 25% in two years. The annualized ROI, or compound annual growth rate (CAGR), gives the constant yearly rate that turns the amount invested into the final value:

Annualized ROI = (final value ÷ amount invested)^(1 ÷ years) − 1

• Investment A: $10,000 → $14,000 in 4 years: ROI 40%, annualized 8.78% a year.
• Investment B: $10,000 → $12,500 in 2 years: ROI 25%, annualized 11.80% a year.

B is the better investment even though its ROI is lower. That is why, when every investment has a duration, the tool picks the Best investment by annualized ROI; if a duration is missing, it compares the simple ROI instead. For less than a year, the annualized rate extrapolates the gain: 5% in six months becomes 10.25% a year, which can overstate short-term results.

Limits of a simple ROI

• It ignores intermediate cash flows. If you added or withdrew money along the way, an internal rate of return (IRR) is more accurate.
• It does not measure risk: two investments with the same ROI can have very different volatility.
• It does not adjust for inflation or taxes; compare after-tax results when accounts are taxed differently.

The results are estimates to help you compare, not investment advice.