Compound interest savings calculator

This calculator shows how your savings can grow over time thanks to compound interest. Enter a starting amount, an optional monthly contribution, the interest rate, and how many years you will save for. It projects your final balance and splits it into the money you contributed and the interest you earned.

The power of compounding

Compound interest means you earn interest not only on your original savings but also on the interest already added. Over many years this snowball effect becomes powerful — which is why starting early and contributing regularly matters far more than the exact rate. The calculator compounds monthly and adds your contribution each month for a realistic projection.

Using it for goals

Use it to plan for a house deposit, an emergency fund, or any savings goal. For longer-term retirement planning, our investment & retirement calculator projects a pension pot, and the budget calculator helps you find money to save each month.

Frequently asked questions

Does it account for tax or inflation?

No. It shows growth before tax and in today's money. Tax-free accounts (like an ISA) and inflation will both affect your real result.

Disclaimer: This calculator provides estimates for informational purposes only and is not financial advice. Investment returns are not guaranteed and the value of investments can fall as well as rise.