Investment calculator: work out return scenarios

Before investing a single euro it helps to understand what time can do to your money — for better and for worse. This calculator works out hypothetical scenarios of periodic contributions. They are mathematical assumptions, not promises: no scenario guarantees anything.

Calculate your scenario

Monthly contribution (€) Years Hypothetical annual return (%)

Estimated scenario based on the assumption entered, with monthly compound interest and excluding taxes, fees and inflation. It is not a promise or a forecast: the real return may be lower, zero or negative.

How to read these scenarios

Compound interest makes constant contributions grow in a non-linear way: the final years weigh far more than the first ones. But market returns are not constant: there are good years, bad ones and very bad ones. A 5% annual scenario is a useful simplification for thinking, not a description of what will happen.

Risk does not appear in the formula

Two portfolios with the same average return can be experienced very differently: one with 40% drops along the way and another with no shocks. Before focusing only on the final result, understand volatility and read our risks page. And remember: past performance does not guarantee future results.

The next step: analyse before investing

A calculator tells you what would happen if. Deciding where requires analysis: which assets stand out, what analysts with a verifiable record say and what consensus there is. That is exactly what GrandAlpha organises: start with the predictions or the stock ranking.

Frequently asked questions

How much would I have if I invest 100 euros a month?

It depends on the real return you get, which no one can guarantee. With the calculator you can work out hypothetical scenarios at different time frames and percentages, as a reflection tool.

Does the calculator predict how much I will earn?

No. It works out a mathematical assumption with the return you enter. The real return may be lower, zero or negative.

What return should I enter?

Whatever you want to explore as an assumption. As a historical reference, the major indices have averaged single-digit annual returns over the very long term, with huge variations along the way. The past does not guarantee the future.

See it for yourself

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