Compound Interest Calculator
See how your money grows over time with the power of compounding.
The Power of Compounding
Einstein reportedly called compound interest the "eighth wonder of the world." The key insight: you earn returns not just on your initial investment, but on all the returns you've already earned. Over long periods, this creates exponential growth.
What This Calculator Does
This calculator shows the power of compound interest by projecting how an initial deposit plus regular contributions grows over a chosen time period. It is designed for savers and investors wanting to see how their money could grow over time.
How the Calculation Works
It applies the compound interest formula, reinvesting earnings at regular intervals. You can choose monthly or annual compounding and adjust the interest rate, initial amount, and monthly contributions.
Common Scenarios
Investing £200/month at 7% annual return for 30 years would grow to roughly £243,000 (from £72,000 contributed). Even small changes in rate or time have a dramatic effect: the same contributions at 5% would produce around £167,000.
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