ROI Calculator South Africa 2026
Calculate Return on Investment for any business or property investment
ROI calculations are based on estimates. Actual returns may vary.
Frequently Asked Questions
Is this calculator free to use?
Yes, all SumZA calculators are completely free with no registration required.
Are the results accurate?
We use the latest SARS tax brackets, BCEA regulations, and Eskom tariffs. Results are estimates for guidance only.
Can I share my results?
Yes, you can print or screenshot your results for personal reference.
Do you store my data?
No, all calculations happen in your browser. We do not see or store your inputs or results.
How often are the rates updated?
We update our rates when SARS, the SARB, or other authorities announce changes. Check the page for the current rate effective dates.
What if I get a different result from SARS?
This calculator provides estimates. For official calculations, consult SARS or a registered tax practitioner.
Can I use this for business purposes?
These calculators are for guidance. For business or tax decisions, consult a qualified professional.
Is this calculator official?
No, SumZA is an independent tool. It is not affiliated with SARS, banks, or government departments.
Does this work on mobile?
Yes, all SumZA calculators are mobile-responsive and work on any device.
Who built SumZA?
SumZA is built for South Africans by South Africans, to make financial calculations simple and accessible.
How the ROI calculator works
Return on investment = (gain from the investment − cost of the investment) ÷ cost of the investment × 100. The trap is what counts as a gain: revenue is not a gain, profit is.
Spend R30 000 and receive R45 000 back: the ROI is (R45 000 − R30 000) ÷ R30 000 = 50%.
That is a total return over the period, not an annual one. Spread over three years it is 16.7% a year simple, or 14.5% a year compounded — the two figures are not the same, and the compounded one is the honest one.
What changes the answer in South Africa
ROI ignores timing, which is why a 30% return over ten years is poor and a 30% return over six months is excellent. Use the internal rate of return or the annualised figure when comparing options, and always state whether the return is before or after tax — for a business, the after-tax figure is the one that matters.
Common questions about the ROI calculator
Is ROI the same as profit?
No. Profit is the rand amount left; ROI expresses that amount as a percentage of what was invested, which is what allows comparison between different-sized projects.
Should ROI be annualised?
Yes, if you are comparing investments of different lengths. A 30% total return means nothing until you know over how many years.
Does ROI include the cost of capital?
Only if you include it in the cost. If the money was borrowed at 11%, an ROI of 9% is a loss once finance is counted.