A self-possessed adult woman in a clean, high-end editorial setting for Compound Interest.

01 / 25 · Compound Interest

Her company car has a driver. When does your money start working for you?

Compounding does almost nothing early and almost everything late. Most people quit during the boring part.

The lesson

Money can earn money. Then that money earns money too.

€10,000 left alone at 8% a year becomes €21,589 in ten years. You did nothing. The interest earned interest.

The first decade adds €11,589. The third adds €54,017. Same capital. Same rate. More time for every previous gain to participate.

The curve is the lesson: growth begins quietly, then accelerates as the productive base becomes larger.

8% is an illustration, not a forecast. For historical context, MSCI World (gross return, USD) annualised 9.02% from 1987 to July 2026—while its reported maximum drawdown was 57.46%.

€21,589After 10 years

€46,610After 20 years

€100,627After 30 years

Test the curve

Change time. Watch the ending move.

Explore how starting capital, annual growth and time interact.

See the curve

The curve explains
the €100,627.

Compounding looks quiet early because the productive base is still small.

€10,000 at 8%

The curve explains the €100,627.
YEARS INVESTED	€10,000 at 8%
0	10000
10	21589
20	46610
30	100627

Starting capital

Annual growth

Years invested

Ending value

Total growth

Value after first decade

Continue with any AI assistant

Make the curve visible.

Teach me compound interest using €10,000 earning 8%, compounded annually.

Show the value after 10, 20, and 30 years. Separate principal from cumulative growth, compare how much the first and third decades add, and explain why the curve accelerates.

Then repeat at 4% and 10%, state every assumption, and give me three practice questions. Keep it educational, not personalized financial advice.

Assumptions

Constant 8% annual return, compounded annually.
No fees, taxes, withdrawals or additional contributions.
Figures are rounded to the nearest euro.
Illustrative only. Returns are not guaranteed.
Historical context only: MSCI World Index (gross, USD) annualised 9.02% from Dec 31, 1987 to Jul 31, 2026; reported maximum drawdown 57.46%. Source: MSCI World Index factsheet.