ROI Calculator — Return on Investment
Updated: 2025
Calculate your return on investment (ROI) instantly. Includes annualised ROI and payback period.
What is ROI?
Return on Investment (ROI) is a measure of the efficiency or profitability of an investment. It is expressed as a percentage: the net gain divided by the cost of the investment. ROI is used in business to evaluate the performance of investments, marketing campaigns, equipment purchases, and more.
ROI Formula
ROI (%) = (Return - Cost) / Cost × 100. A 50% ROI means you made 50p profit for every £1 invested. A negative ROI means the investment lost money. Annualised ROI allows you to compare investments of different lengths on an equal basis.
What is a Good ROI?
A good ROI depends on context. For stock market investments, 7-10% annualised is considered good historically. For business investments, a rule of thumb is that projects should return at least 15-20% ROI to be worth pursuing over simply holding cash. Marketing ROI benchmarks vary widely by channel.