How the Percentage Return Calculator works
Percentage return measures how much an investment gained or lost relative to what you originally put into it. It answers a simple question — "for every dollar I invested, how many cents did I gain or lose?" — in a way that works whether you invested $100 or $1,000,000, which is what makes it useful for comparing very different investments side by side.
The formula
For an Initial Value (what you paid), a Final Value (what it is worth now or when sold), and any Income received along the way (dividends, interest, or distributions), the total gain and percentage return are:
Total Gain = Final Value + Income − Initial Value
Return % = (Total Gain ÷ Initial Value) × 100
To compare holdings of different lengths on equal footing, the calculator also annualizes the result using CAGR-style compounding:
Annualized Return % = (((Final Value + Income) ÷ Initial Value)1/Years − 1) × 100
When the holding period is exactly one year, the annualized return and the total percentage return are the same number.
Worked example
Suppose you bought shares for $10,000, they are now worth $13,500, and you collected $250 in dividends along the way over a 2-year holding period. The total gain is $13,500 + $250 − $10,000 = $3,750, a percentage return of $3,750 ÷ $10,000 = 37.5%. Annualizing that over 2 years — (($13,750 ÷ $10,000)1/2 − 1) × 100 — gives roughly 17.3% per year, meaning a steady 17.3% annual gain compounded over 2 years would produce the same result.
What moves the return most
- Final value versus initial value: this is the core driver — the bigger the gap between what you paid and what it is worth now, the bigger the percentage return in either direction.
- Income received: dividends and interest add directly to the total gain. Leaving them out understates the true return, especially for income-focused investments like bonds or dividend stocks.
- Holding period: a 37.5% total return earned in 6 months is a very different result from the same 37.5% earned over 10 years — annualizing makes that difference explicit.
What this calculator does not account for
This is a straightforward holding-period-return calculation: it does not adjust for taxes, transaction fees, or inflation, and it assumes income was simply added to the final value rather than reinvested at a specific date. For results involving irregular contributions or withdrawals over time, a money-weighted return (like XIRR) is more appropriate than this simple formula.