How to use this calculator
The blue cells are editable. Click any value and type in your own number. The results update immediately, and the chart redraws as you go.
Understanding each input
Current fund value
This is the amount you already have saved or invested today. If you're starting from scratch, leave this at zero.
Monthly contribution
How much you plan to add each month. Contributions in this calculator are treated as payable in advance, meaning each contribution is made at the start of the month, consistent with how most South African investment products work.
Yearly growth rate of contributions
If you plan to increase your monthly contribution each year, enter the percentage here. For example, if you set this to 5%, a R1,000 monthly contribution becomes R1,050 in year two, R1,102.50 in year three, and so on. This is sometimes called a contribution escalation rate.
Investment term
How many years you plan to keep the money invested. The longer the term, the more powerfully compound interest works in your favour.
Investment return (effective annual rate)
The return you expect your investment to earn per year, expressed as an effective annual rate. This is the rate after compounding has been applied, and is the standard way South African financial institutions quote investment returns.
As a rough guide for South Africa:
| Investment type | Typical effective annual return |
|---|---|
| High-interest savings account | 7% to 9% |
| Fixed deposit (1 to 3 years) | 8% to 10% |
| Balanced fund (Regulation 28) | 8% to 10% |
| JSE All Share Index (20-year average) | approx. 10% to 12% |
| Money market fund | 7% to 8% |
These are illustrative ranges only. Actual returns vary and are not guaranteed. For planning purposes, using a conservative rate is always advisable.
Inflation rate
The "FV in today's money" result adjusts your future value for inflation, so you can see what that amount would actually be worth in today's purchasing power terms. South Africa's average inflation rate has been around 5% to 6% per year historically. The default in the calculator is 6%.
A note on the maths
This calculator uses the effective annual rate to derive the monthly compounding rate using the formula (1 + annual rate)^(1/12) - 1. Contributions are applied at the start of each month and the contribution growth rate is applied once annually. This approach is consistent with the Sanlam Life compound interest calculator and standard South African actuarial practice.
Frequently asked questions
What is the difference between the two calculator modes?
Future value tells you what a given savings plan will grow to. Required contribution works backwards from a target amount and tells you how much you need to save monthly to get there.
Can I use this calculator for retirement planning?
Yes. Enter your current retirement savings as the starting fund value, your expected monthly contribution, and the number of years until retirement. Use three scenarios to model different return assumptions — conservative, moderate, and optimistic.
What does "FV in today's money" mean?
It shows you what your future value is worth in today's purchasing power, after accounting for inflation. R1 million in 20 years is not the same as R1 million today. At 6% inflation, it would be worth roughly R312,000 in today's terms. This is why the inflation-adjusted figure matters.
Why does increasing my monthly contribution by a small amount make such a big difference?
Because every additional rand you invest today compounds over your entire remaining investment term. An extra R500 a month invested over 20 years at 9% doesn't just add R120,000. It adds all the returns that R120,000 would have generated over those 20 years too.
Is this calculator free?
Yes, completely free. No login, no sign-up, no data stored. ClearCents exists to help South Africans make more informed decisions about saving and investing.