Inflation Impact Calculator
See how inflation erodes your money's purchasing power over time.
Last reviewed: Source: StatsSA — Consumer Price Index
Inflation as a tax you can't opt out of
Inflation is the quiet destroyer of savings. Every year, the same rand buys slightly less — and compounded over decades, “slightly less” becomes dramatically less. In SA, where CPI has averaged around 6% over the past decade, the purchasing power of a rand halves roughly every 12 years (rule of 72: 72 ÷ 6 = 12).
That means R1,000,000 stuffed under your mattress in 2026 has the spending power of about R500,000 in 2038 money, and about R250,000 by 2050. It’s not the mattress that’s losing value — it’s the currency.
SA CPI history — it's not always 6%
| Period | Average CPI |
|---|---|
| 1980s | ~14% |
| 1990s | ~10% |
| 2000–2005 | 5–7% |
| 2006–2008 (food shock) | 9–12% at peaks |
| 2009–2016 | 4.5–6% |
| 2017–2019 | 4–5% |
| 2020–2021 (pandemic) | 3–4.5% |
| 2022–2023 (war + energy) | 6.5–7.5% at peaks |
| 2024–2026 | 4.5–6% |
For planning purposes, use 6% long-term CPI unless you have a reason to model differently. That’s roughly SARB’s mid-band and matches the 10-year average.
Nominal vs real — the only thing that matters in the long run
Nominal return is the headline number. Real return is nominal minus inflation — the actual increase in your purchasing power. Most people unconsciously reason in nominal terms, which makes long-term plans look rosier than they are.
| Nominal return | Inflation | Nominal future value | Real future value (today’s R) |
|---|---|---|---|
| 10% | 6% | R17,450,000 | R3,050,000 |
| 12% | 6% | R29,960,000 | R5,230,000 |
| 8% | 6% | R10,060,000 | R1,760,000 |
| 6% | 6% | R5,740,000 | R1,000,000 (flat) |
| 4% | 6% | R3,240,000 | R565,000 (losing purchasing power) |
A 10% nominal return looks great. It’s really a 3.77% real return ((1.10/1.06) − 1). Over 30 years you triple your purchasing power — not 17×. Still good, but recalibrate the expectation.
Worked examples
R1,000 today = what in 2046 at 6% inflation?
Buying power of R1,000 in 2026 versus nominal equivalent in 20 years.
- Starting amount
- R1,000
- Inflation
- 6% per year
- Years
- 20
- Inflation multiplier = 1.06²⁰
- 3.207
- Nominal equivalent in 2046
- ≈ R3,207
Retirement income target erosion
Planning R30,000/month lifestyle in retirement, 20 years from now, 6% inflation.
- Today’s target
- R30,000/month
- In 20 years at 6%
- ≈ R96,210/month
- Annualised
- ≈ R1,154,520/year
- Needed capital (4% safe withdrawal)
- ≈ R28,860,000
R5,000,000 cash for 30 years — unmanaged
Inheritance kept in a current account earning 0%. 6% inflation.
- Starting capital
- R5,000,000
- Nominal value in 30 years
- R5,000,000 (no return)
- Real purchasing power (divide by 1.06³⁰ = 5.74)
- ≈ R871,000
Which assets actually beat inflation
| Asset | Typical nominal | Typical real (after 6% CPI) |
|---|---|---|
| Cash / money market | 8–10% | 2–4% (barely positive) |
| SA bonds (ALBI) | 10–12% | 4–6% |
| SA equities (JSE Top 40) | 10–13% | 4–7% |
| Global equities (ZAR) | 9–12% | 3–6% (includes currency effect) |
| Balanced fund (Reg 28) | 9–11% | 3–5% |
| Residential property (capital only) | 6–8% | 0–2% |
| Gold | 6–8% (very volatile) | 0–2% |
Over 20–30 year horizons, equities comfortably beat inflation. Over 5-year windows, equities can underperform cash. That’s the core reason retirement money belongs in equities and emergency money belongs in cash.
Inflation compounds. So does indexation.
SARS indexes most tax thresholds annually (the primary rebate, tax brackets, TFSA limit, transfer duty thresholds). This protects taxpayers from “bracket creep” — moving into a higher bracket because your salary grew with inflation, not because you got richer in real terms.
But SARS doesn’t always index annually. The retirement contribution cap sat at R350,000 from 2016 to Budget 2026 — no inflation adjustment for 10 years. Income tax brackets were frozen between 2023/2024 and 2025/2026. Over a decade of inflation without indexation, effective tax burdens rise meaningfully.
Practical takeaway: if you’re doing long-horizon financial planning, don’t assume today’s tax-free thresholds will still apply in 2046 in real terms. Plan for some real-terms erosion.
How this calculator works
Enter an amount, an inflation rate (default 6% for SA), and a number of years. The calculator returns both (a) the nominal amount you’d need in the future to match today’s purchasing power, and (b) the present purchasing power of a future amount. Useful for retirement-income planning, education-savings targets, and stress- testing long-term cashflow assumptions.
Sources
Frequently Asked Questions
Inflation is the rate at which prices rise over time, reducing the purchasing power of money. If inflation is 5% per year, something that cost R100 today will cost R105 in a year.
South African inflation varies by year. Recent inflation has been 4–8% per year. The central bank targets 3–6%. Check the SARB website for current official rates.
Invest in assets that grow faster than inflation: equities, property, bonds, or inflation-linked savings. Money left in savings accounts (2–3% return) loses value to inflation.
Your retirement fund must grow faster than inflation. If you retire with R2 million and inflation averages 5%, your purchasing power is halved in 14 years. Plan for real (inflation-adjusted) returns.