Compound interest calculator
See how your savings grow when interest is added on top of interest, with optional monthly deposits.
About this calculator
Compound interest means you earn interest on your interest as well as on your original money. Enter a starting amount, how much you add each month, the yearly rate and the number of years, and choose how often the interest is compounded.
The longer you leave money, the bigger the effect, which is why starting early matters. The figures are not adjusted for inflation or tax.
Common questions
How often is interest compounded?
It depends on the account. Savings are often compounded monthly or yearly, so check yours.
Does it include tax?
No. Interest may be taxable, though ISAs shelter it in the UK.
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