💰 Compound Interest Calculator

Calculate how your investments and savings will grow over time with compound interest

£
£

Additional amount you add each month

%

Average stock market return is about 7-10%

years

How often interest is calculated and added

Quick Examples:

See Your Investment Growth

Fill out the form and click "Calculate Growth" to see how compound interest can work for you.

Understanding Compound Interest

What is Compound Interest?

Compound interest is "interest on interest." When you earn interest on your investment, that interest is added to your principal. Next period, you earn interest on the new, larger amount. This creates exponential growth over time.

The Formula:

A = P(1 + r/n)nt + PMT × [((1 + r/n)nt - 1) / (r/n)]

Key Tips

  • • Start Early: Time is your biggest advantage with compound interest
  • • Be Consistent: Regular contributions, even small ones, add up significantly
  • • Higher Frequency: Monthly compounding usually beats annual
  • • Stay Patient: The most dramatic growth happens in later years