Compound Interest Calculator
Worked example (the default inputs above): €10,000 starting amount, €200 a month, 5% a year, 10 years, monthly compounding → about €47,656, of which €34,000 was paid in and about €13,656 is growth.
Key fact: Time beats timing: starting 10 years earlier usually matters more than finding a slightly higher return, because returns compound on past returns.
What this calculator does
This calculator shows what regular saving could grow to when returns compound — each year's returns earn returns of their own in later years. Enter a starting amount, a monthly contribution, an expected annual return and a time horizon, and it shows the projected balance year by year.
→ Retirement savings calculator
How to use it
- Enter your starting amount (0 if you are starting from scratch).
- Enter your monthly contribution.
- Enter an expected annual return — 5% is a common long-run illustration for diversified investing, not a promise.
- Choose how often interest is credited and your time horizon, then read the year-by-year balance.
→ Saving money as an expat in Europe
The formula
Each month, your contribution is added, and at each compounding date the balance grows by rate ÷ compounding periods per year. Over time this is the same compounding that makes the formula FV = P(1+i)n + PMT × ((1+i)n − 1) ÷ i work, where i is the rate per compounding period and n is the number of periods.
→ Business loan EMI calculator
Worked example with real numbers
An expat in Amsterdam starts with €10,000, saves €200 a month, and earns an assumed 5% a year, compounded monthly. After 10 years she has paid in €34,000 in total and the balance is about €47,656 — roughly €13,656 of growth. Stretch the same habit to 20 years and the balance reaches about €109,676 on €58,000 paid in, because the second decade's growth builds on the first decade's balance. At 3% instead of 5%, the 10-year balance is only about €41,512 — a reminder that the assumed return drives the answer, and real returns vary year to year.
→ Retirement savings calculator
Reference table
What €200 a month from €10,000 could reach at different returns (10 years — illustrative figures, returns not guaranteed):
| Annual return | Balance after 10 years | Growth |
|---|---|---|
| 2% | €38,800 | €4,800 |
| 5% | €47,656 | €13,656 |
| 7% | €54,916 | €20,916 |
→ Brokers in Europe for expats
Sources and disclaimer
Method: month-by-month compounding at the rate and frequency you select. The return you enter is an assumption, not a forecast: investment returns vary, can be negative, and past performance does not predict future results. Inflation is not deducted here — a balance of €47,526 in 10 years buys less than €47,526 today. Tax on investment income varies by country of residence.
Estimate only — not tax or financial advice. This tool estimates only. It is not tax, legal or financial advice and does not determine your actual tax, loan or lender decision — check your national tax authority, bank or a qualified adviser for your situation. Always verify current figures with the official source or a qualified adviser before making decisions.
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