ROI Calculator
Work out the return on investment (ROI) for money you have already invested, based on what you put in and what you got back.
The amount you originally put in — e.g. the purchase price, or the amount you invested.
Any extra money spent to acquire, improve, or maintain the investment — e.g. fees, renovation costs, or transaction charges. Leave as £0 if none.
What the investment is now worth, or what you sold it for.
Any income the investment paid you along the way — e.g. dividends, rent, or interest. Leave as £0 if none.
How long you held the investment. Add this to also see an annualised return — leave blank if you only want total ROI.
Cost, Return & Profit Comparison
Calculation Breakdown
ROI Calculator: Work Out Your Return on Investment
Our ROI Calculator works out the return you have made (or would make) on a specific investment — a property, shares, a business, or any purchase you expect to sell on or that pays you income. Enter what you put in and what you got back, and the calculator shows your profit, your ROI percentage, and, if you supply a holding period, an annualised return as well.
This is different from our Investment Calculator, which projects how a lump sum or regular contributions might grow in the future under an assumed rate of return. Use this ROI Calculator when you already know (or can estimate) the final value and want to measure the return achieved.
ROI Formula
Total Return = Final Value + Income Received
Profit = Total Return − Total Cost Basis
ROI (%) = Profit ÷ Total Cost Basis × 100
ROI measures your total profit relative to what you actually put in — it does not account for how long you held the investment. Two investments can have the same ROI but very different annual performance if one took two years and the other took ten.
How to Calculate ROI
- Add up your total cost basis. Start with your initial investment and add any additional costs — legal fees, renovation costs, brokerage charges, or anything else spent to acquire or maintain the investment.
- Add up your total return. Take the final value (what it’s worth now, or what you sold it for) and add any income received along the way, such as dividends, rent, or interest.
- Subtract to find your profit. Total return minus total cost basis gives you your profit — or loss, if the figure is negative.
- Divide by the cost basis and multiply by 100. This gives you your ROI as a percentage.
- Optional: add a holding period if you want to see the annualised return alongside the headline ROI figure.
ROI vs Annualised Return: What’s the Difference?
ROI is your total return relative to your original cost basis, over whatever period you held the investment — it treats a one-year gain and a ten-year gain of the same percentage as identical. Annualised return (sometimes called CAGR, or Compound Annual Growth Rate) spreads that return out over time, showing roughly the equivalent compound annual growth rate over the period.
In this calculator, the annualised return is calculated using only your initial investment and final value — it does not factor in additional costs or income received along the way, in line with the standard CAGR approach used across the industry. Because of this, treat it as a broad, comparable yardstick alongside your headline ROI figure, not as a substitute for it. The two figures answer different questions and should not be read as interchangeable.
Worked Examples
| Scenario | Cost Basis | Total Return | Profit / Loss | ROI |
|---|---|---|---|---|
| Shares bought and sold, plus a dividend | £10,500 | £13,500 | £3,000 | 28.57% |
| Property held 5 years, sold at a loss | £220,000 | £205,000 | -£15,000 | -6.82% |
| Small business investment, break-even exit | £50,000 | £50,000 | £0 | 0.00% |
Limitations and Caveats
- This calculator does not account for tax (such as Capital Gains Tax or Income Tax on dividends/rent), which can materially change your real return.
- It does not account for inflation, so a positive ROI over many years may still represent a fall in real purchasing power.
- Ongoing running costs that aren’t entered as “additional costs” (such as mortgage interest, insurance, or management fees) will not be reflected in the result.
- The annualised return uses a simple CAGR calculation based on a single initial sum and a single final value — it does not model multiple cash flows in and out over time, which a fuller IRR (Internal Rate of Return) calculation would.
- Figures are only as accurate as the values you enter — this tool provides an estimate for guidance and is not financial advice.
Frequently Asked Questions
What is ROI and how is it calculated?
ROI (Return on Investment) is your profit expressed as a percentage of what you put in. It’s calculated as profit divided by total cost basis, multiplied by 100, where profit is your total return minus your total cost basis.
What’s the difference between ROI and annualised return?
ROI is your total return over the whole period you held the investment, with no adjustment for time. Annualised return (CAGR) spreads that return out to show an approximate yearly rate, which makes it easier to compare investments held for different lengths of time.
How is this different from the Investment Calculator?
This ROI Calculator looks backward: you enter what you put in and what you got out, and it tells you the return achieved. The Investment Calculator looks forward: you enter an assumed growth rate and it projects how your money might grow in future.
Can ROI be negative?
Yes. If your total return is less than your total cost basis, the calculator will show a negative ROI, reflecting a loss on the investment.
Does this calculator account for taxes or fees?
Only if you include them yourself. Any fees, charges, or costs involved in acquiring or maintaining the investment should be entered under “Additional Costs” so they’re reflected in the total cost basis. The calculator does not automatically apply tax rates such as Capital Gains Tax.
What should I include as “additional costs”?
Any money spent on top of the initial investment to acquire, improve, or hold it — for example, legal fees, stamp duty, renovation costs, brokerage fees, or transaction charges.
What counts as “income received”?
Any money the investment paid you while you held it, separate from its final sale value — for example, dividends from shares, rental income from property, or interest payments.
Is a higher ROI always better?
Not necessarily on its own. A high ROI achieved over ten years is a very different result to the same ROI achieved in one year. That’s why this calculator also shows an annualised return when you provide a holding period, so you can compare investments on a more like-for-like basis.