Countwell

ROI Calculator

Put a number on how well an investment did, comparing what you put in with what it is worth now.

Last updated: August 5, 2026

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Return on investment
Gain
Annualised return (if years given)

What is return on investment?

Return on investment, or ROI, is the simplest way to answer the question: did this make money, and how much, compared with what I put in? It expresses your gain as a percentage of the amount invested, so a small investment that doubled looks the same as a large one that doubled.

The gain is the current value minus what you invested. ROI is that gain divided by the investment, shown as a percentage. If the current value is lower than you invested, ROI is negative and the calculator shows a loss.

If you enter how many years you held the investment, the calculator also shows an annualised return. That smooths the growth into a yearly percentage, which makes it fair to compare investments held for different lengths of time.

The formula

ROI (%) = (current value − amount invested) ÷ amount invested × 100
Annualised ROI (%) = ((current ÷ invested) ^ (1 ÷ years) − 1) × 100

Worked example

You invest $5,000 and it is now worth $6,250 after 3 years.

Gain = $1,250. ROI = 1,250 ÷ 5,000 × 100 = 25%.

Annualised = (6,250 ÷ 5,000)^(1 ÷ 3) − 1 ≈ 7.7% per year.

Simple ROI overstates short-term wins, which is why the annualised figure is the honest one to compare against other opportunities.

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Frequently asked questions

What is a good ROI?

It depends entirely on the time period and the risk. A broad stock index has historically returned roughly 7–10% a year before inflation. Compare any investment against what you could earn elsewhere with similar risk.

Does this include fees and taxes?

No. If you paid fees or taxes on the gain, subtract them from the current value before entering it, so the result reflects what you actually walk away with.

Why is annualised return different from ROI?

ROI shows the total result over the whole period. Annualised return spreads that result into a per-year percentage, so a return earned in one year can be compared fairly with one earned in ten.

This calculator gives an estimate only and is not investment advice. Past performance does not predict future results.