Compound Interest Calculator

Enter your starting amount, monthly contribution, yearly interest rate and number of years. The calculator shows the final value of your savings when interest compounds every month.

This result is an estimate only. Check with your bank or the relevant authority before making decisions.

How it is calculated

Interest compounds every month and contributions are made at the end of each month.

r = yearly rate ÷ 1200
n = 12 × number of years
Final value = starting amount × (1 + r)^n + monthly contribution × ((1 + r)^n − 1) ÷ r
Total contributions = starting amount + monthly contribution × n
Total interest = final value − total contributions

If the rate is 0%, final value = starting amount + monthly contribution × n.

Worked example

Starting amount RM10,000, RM200 a month, 4% a year, for 10 years:

Final value: RM44,358.29
Total contributions: RM34,000.00
Total interest: RM10,358.29

Why your number may differ

The calculator assumes a fixed rate for the whole period, while real returns vary. A real product may calculate interest or accept contributions in a different way.

Frequently asked questions

When is the monthly contribution counted?

Contributions are assumed to be made at the end of each month, after that month's interest is added.

Is the interest rate always fixed?

The calculator assumes a fixed rate. Real returns vary, so the result is only an estimate.

What happens if the rate is 0%?

No interest is added, so the final value is the starting amount plus all the monthly contributions.