Investing
Compound Interest Calculator
See how an initial investment plus regular monthly contributions could grow over time in Swiss francs. Adjust the return and inflation assumptions to understand the range of possible outcomes — all results are estimates.
Estimated value after 20 years
CHF 233'500
Approximately CHF 183'940 in today's purchasing power at 1.2% inflation.
Total contributions
CHF 130'000
Initial amount plus all monthly payments
Estimated investment gains
CHF 103'500
44.3% of the final value
Inflation-adjusted value
CHF 183'940
In today's francs
Contributions vs. growth
The dark area is money you paid in. The green area is the estimated growth on top of it.
After 10 years
CHF 94'435
CHF 83'816 in today's francs
After 15 years
CHF 155'338
CHF 129'889 in today's francs
After 20 years
CHF 233'500
CHF 183'940 in today's francs
What these numbers mean
Compound interest means your returns start earning returns themselves. In this projection you pay in CHF 130'000 in total, and the estimated growth on top of that is CHF 103'500 — that is 1.80× your contributions after 20 years, an effective 2.97% per year on the money you invested.
Inflation quietly reduces what your money can buy. At 1.2% inflation, CHF 233'500 in 20 years would feel like about CHF 183'940 today. This is why holding everything in a Swiss savings account with a low interest rate can lose purchasing power over long periods.
Real markets do not deliver a smooth annual return. A realistic way to use this tool is to run a pessimistic case (for example 3%), a base case (5%) and an optimistic case (7%) and treat the spread as the plausible range.
Assumptions used
- Returns are assumed to be constant every month — real markets fluctuate, sometimes heavily.
- Monthly contributions are compounded monthly using the annual return divided by twelve.
- No product costs, fund fees, custody fees, trading fees or spreads are deducted.
- No Swiss taxes are modelled: Swiss capital gains on private assets are generally tax-free, but dividends and interest are taxable income and wealth tax may apply.
- Inflation-adjusted values use a constant inflation rate to express the final amount in today's purchasing power.
- Amounts are in Swiss francs (CHF); currency risk of foreign investments is not modelled.
This calculator provides approximate, educational estimates only. It is not investment advice, a forecast, or a guarantee of future returns, and it does not consider your personal situation, fees or tax position. Your inputs stay in your browser and are never sent to a server.
Frequently asked questions
Short answers to the questions that come up most often with this calculator.
- How is compound interest calculated here?
- Your initial amount grows at the expected annual return, and each monthly contribution is added and then compounds for the remaining months. Returns are applied monthly at one twelfth of the annual rate, which is a standard simplification.
- What return should I assume for a Swiss portfolio?
- There is no correct number. A common approach is to run a pessimistic case around 3%, a base case around 5% and an optimistic case around 7%, then treat the spread as the plausible range rather than trusting a single figure.
- Why does the inflation-adjusted value matter?
- It translates the final amount into today's purchasing power. A portfolio that grows 4% per year while inflation runs at 1.5% only gains about 2.5% in real terms, which is what actually determines what you can buy later.
- Are fees and taxes included?
- No. Enter a return that is already net of fund costs and platform fees if you want a realistic figure. Swiss wealth tax and tax on dividends are not modelled in this tool.