Performance measurement

Investment return calculator

Separate contributed cash from investment gain and calculate comparable return measures.

How investment return is calculated

Total gain equals ending value plus income received outside the account, minus the starting value and additional contributions. ROI divides that gain by total contributed capital. This prevents deposits from being mistaken for investment growth and includes distributions that were not reinvested.

CAGR requires a simple cash-flow pattern

When there are no additional contributions, the calculator reports compound annual growth rate using the beginning value, ending value plus outside income, and holding period. Once money enters at different dates, that shortcut is not a valid annualized return. The result then explains that a time-weighted return or an internal-rate-of-return calculation needs dated cash flows.

Use consistent valuation dates

Use account values from the exact beginning and ending dates. Include fees already deducted from the account in those values. Record dividends, interest, and other distributions under outside income only when they are not already included in the ending balance, otherwise they would be counted twice.

ROI and investor experience are different questions

Simple ROI shows gain relative to contributed capital but ignores when contributions occurred. A contribution made near the end did not have the same time to grow as one made near the beginning. Portfolio reporting may use money-weighted or time-weighted methods depending on whether the goal is measuring the investor’s experience or the investment manager’s performance.

Nominal return is not purchasing-power return

The output does not adjust for inflation, taxes, trading costs outside the account, or changes in currency value. Compare the result with the inflation calculator when purchasing power matters, and use after-tax cash flows when evaluating what you actually retained.

Separate measurement from forecasting and tax

This page measures a completed holding period. Use the Compound Interest Calculator only when projecting an assumed future rate, and use the 2026 Long-Term Capital Gains Tax Calculator for a separately supported federal tax estimate. A return percentage alone does not reveal risk, liquidity, fees, tax character, or whether the result met the household plan.

This calculator provides general educational arithmetic, not investment, financial, tax, accounting, or legal advice. Past return does not predict future performance, and a positive result does not establish that an investment was suitable or sufficiently compensated for risk.