Compound interest calculator
See how a deposit and regular contributions grow with monthly, quarterly, yearly or daily compounding.
The tax rate is a typical flat rate on interest for the selected country and is only an example — real rules differ and this is not tax advice.
With 0 % the tax depends on your personal situation, so enter your own rate.
Everything is recalculated while you type; nothing is sent anywhere.
Balance year by year
Contributions Interest after tax Final balance after tax
Yearly breakdown
| Year | Contributions | Interest | Tax | Balance |
|---|
How to use the compound interest calculator
- Pick your country so the currency and a typical tax rate on interest are filled in for you.
- Enter the initial deposit, the regular contribution and how often you add it.
- Set the annual interest rate and how often interest is compounded.
- Choose the number of years, adjust the tax rate and its mode, and add inflation if you want a real value.
- Read the result cards, the chart and the yearly table, then copy the table into a spreadsheet.
When it helps
- Checking what a savings account or a term deposit will be worth in ten years.
- Comparing monthly and yearly compounding on the same rate.
- Seeing how much of the final balance comes from your own contributions and how much from interest.
- Estimating the tax on interest before you withdraw the money.
- Checking whether a long-term plan keeps up with inflation.
Frequently asked questions
What is compound interest?
Interest is added to the balance, and the next period earns interest on that larger amount. Over many years the difference from simple interest becomes large.
How much difference does compounding frequency make?
More frequent compounding gives slightly more. At 5 % a year, 10 000 grows to about 16 289 with yearly compounding and about 16 470 with monthly compounding over ten years.
Do regular contributions matter more than the rate?
Both matter, but contributions are money you control. Paying in 100 a month at 6 % for ten years gives about 16 388, of which 12 000 is your own money.
What do the two tax modes mean?
Withheld each time means tax is taken from every interest credit, so the taxed money never earns more interest. Deducted at the end means the whole balance grows gross and tax is subtracted once at the end, which usually leaves a little more.
Why does inflation matter?
Inflation reduces what the final balance can buy. The real value divides the net balance by the cumulative inflation over the whole period, so you see the result in today's money.
Are the tax rates shown correct for my country?
They are typical flat rates used as examples only. Real rules depend on the product and on your personal situation, so check with a tax adviser before relying on them.