Investment Calculator
Measure gain, loss, and percentage return on an investment. Your work stays on this device whenever possible.
How to use Investment Calculator
- Enter what you put in under Initial Investment ($) and what it is worth now under Ending Portfolio Value ($).
- Fill Holding Duration (Years); decimals such as 2.5 are accepted.
- Add Estimated Annual Inflation (% optional) to obtain a real, inflation-adjusted yearly return.
- Choose a Compare Against Benchmark option, for instance the S&P 500, savings or real estate, or select No Benchmark.
- Press "Calculate investment return" and use "Copy Summary" to save the ROI, CAGR and projection lines.
Worked example
Enter start 8,000, end 11,000, 4 years, inflation 3%, benchmark S&P 500. Gain is +3,000.00 and ROI 37.50%. CAGR = (11,000 ÷ 8,000)^(1/4) − 1 = 8.29%, and the real return is 1.0829 ÷ 1.03 − 1 = 5.13%. The 10% benchmark grows 8,000 to 11,712.80, so the result trails by 712.80, or 1.71% a year.
When to use this tool
- Converting a total gain on a fund into a yearly rate to compare with another holding period.
- Checking whether a property sale beat a savings account after adjusting for inflation.
- Reviewing a five-year stock position against a fixed benchmark.
Important limitations
Calculates historical holding period return and Compound Annual Growth Rate (CAGR). Does not predict future market performance, capital gains taxes, or brokerage transaction commissions.
Frequently asked questions
What is the difference between ROI and CAGR?
ROI is the total gain as a percentage of the initial amount. CAGR spreads that growth into a steady yearly rate, so a 37.5% total over four years is about 8.29% a year, which lets you compare holding periods.
Are the benchmark rates live data?
No. They are fixed long-run averages built into the page: about 10% for equities, 4.5% for savings and 8% for real estate. Actual returns in any given period differ, so use them as rough yardsticks.
Can this handle regular deposits or withdrawals?
Yes, if the dates and amounts are known: the page's XIRR tool (below the main calculator) solves the money-weighted annual return for a pasted list of dated cash flows using Newton's method, separate from the simple start/end ROI and CAGR above.
How is the real return worked out?
The nominal CAGR is divided by one plus inflation, minus one. With 8.29% nominal and 3% inflation the real figure is about 5.13%, less than the simple subtraction of 5.29%.
Are the 5 and 10 year projections predictions?
No. They extend the same CAGR from the ending value, assuming the past rate continues. Markets do not behave that way, so read them as a what-if, not a forecast.