ROI Calculator

ROI (Return on Investment) is the percentage return earned on money you put in. The calculator uses the standard formula ROI = (Gain − Cost) ÷ Cost × 100, giving you a clean percentage that's directly comparable across investments of different sizes.

Because ROI is a total return, it's most useful for one-off or short-term investments. For multi-year investments where the timing of cash flows matters, IRR (Internal Rate of Return) is a more accurate measure. As a quick fix for multi-year comparisons, you can annualise ROI using the formula Annualised ROI = (1 + ROI)^(1/years) − 1.

In South Africa, long-term equity returns on the JSE have averaged around 12% p.a. nominally, property tends to sit lower with substantial regional variation, and money-market products currently pay 7–9%. ROI does not adjust for tax or inflation — capital gains and dividend taxes reduce your net return, and CPI erodes the real value of gains. Use our Inflation Calculator alongside ROI for a real-terms view.