Compound Interest Calculator UK
Calculate how your savings or investments could grow over time with compound interest and regular monthly contributions. See your projected future value, total contributions and interest earned.
Calculator
What this means
Compound interest means you earn returns not just on your original money but also on the interest already added. Over long periods this snowball effect can make a big difference, especially when you add regular contributions.
Frequently asked questions
Compound interest is interest earned on both your original deposit and the interest already added. The more often interest compounds and the longer you save, the faster your balance grows.
Simple interest is paid only on your original amount. Compound interest is paid on the growing balance, so it accelerates over time — which is why starting early matters so much.
Use the AER on a savings account, or a realistic long-term estimate for investments (often 4–7% before charges and inflation). Investment returns are not guaranteed and can fall as well as rise.
Disclaimer
This calculator provides estimates for guidance only. It is not financial, legal or tax advice. Always check official sources or speak to a qualified professional before making decisions.
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