Compound interest calculator
Calculate the capital obtained from an initial investment, monthly contributions and an annual rate, according to the interest compounding frequency.
Your settings
Results update with each entry.
Paid at the end of each month.
Nominal rate, before taxes and social security contributions.
Frequency at which interest is added to principal and in turn earns interest.
- Principal after 20 years
- €95,581
- Total paid in
- €58,000
- Interest earned
- €37,581
- 39% of final capital
- Annual effective rate
- 4.07%
- Compounded
Capital change
Cumulative amounts at year-end.
- Cumulative contributions
- Cumulative interest
Breakdown by year
| Year | Total paid in | Interest for the year | Cumulative interest | Principal at year-end |
|---|---|---|---|---|
| 1 | €12,400 | €452 | €452 | €12,852 |
| 2 | €14,800 | €568 | €1,020 | €15,820 |
| 3 | €17,200 | €689 | €1,709 | €18,909 |
| 4 | €19,600 | €815 | €2,524 | €22,124 |
| 5 | €22,000 | €946 | €3,470 | €25,470 |
| 6 | €24,400 | €1,082 | €4,552 | €28,952 |
| 7 | €26,800 | €1,224 | €5,776 | €32,576 |
| 8 | €29,200 | €1,372 | €7,148 | €36,348 |
| 9 | €31,600 | €1,525 | €8,673 | €40,273 |
| 10 | €34,000 | €1,685 | €10,358 | €44,358 |
How this calculation is made
The calculation advances month by month. Each month, the capital already compounded earns interest at the monthly rate r / 12, where r is the annual rate entered. This interest accumulates and is then added to the principal at each compounding date: monthly, quarterly, semi-annually or annually, depending on your choice. It then earns interest itself.
Without contributions, we get the standard compound interest formula:
Final capital = C × (1 + r / n)^(n × t)
where C is the initial capital, n the number of compounding periods per year and t the duration in years. The displayed effective annual rate is (1 + r / n)^n − 1.
- Monthly contributions are made at the end of each month and start earning interest the following month.
- The rate is assumed constant over the entire term.
- Taxes, social contributions and any fees are not deducted.
The results are simulations based on the stated assumptions. They do not predict future results and do not take your personal situation into account. The information published on TimeLinq is for informational purposes only and does not constitute investment advice. Investing involves a risk of capital loss.