Compound Interest Calculator
See the true power of compounding over time
Small regular contributions grow significantly over decades. This calculator shows the impact of time, growth rate, inflation, and compounding frequency on your investment.
Projected portfolio value
£292,465
= £178,483 in today's money
Initial investment
£10,000
Total contributions
£130,000
Including £120,000 monthly
Investment growth
£162,465
+125% return
Final value (nominal)
£292,465
Growth over 20 years
| Label | Value |
|---|---|
| Initial investment | £10,000 |
| Total contributions | £130,000 |
| Total growth | £162,465 |
| Final value | £292,465 |
| Real value (inflation-adjusted) | £178,483 |
Rule of 72
At 7% annual growth, your money doubles approximately every 10.3 years. Over 20 years, that's about 1.9 doublings.
Inflation impact
At 2.5% annual inflation, your £292,465 nominal portfolio is worth only £178,483 in today's purchasing power — 39% less.
Investment details
Used to calculate real (today's money) value
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This calculator is for illustrative purposes only. Projected values assume a fixed annual return applied consistently over the full period — real investment returns vary year to year and are not guaranteed. Inflation is not modelled unless specified. Past performance is not a reliable indicator of future results. The value of investments can fall as well as rise. This calculator does not constitute financial advice. Selvox accepts no liability for decisions made in reliance on these outputs.