Compound Interest Visualiser
See how compound interest grows any investment over time. Choose frequency and rate. Shows year-by-year breakdown. Free.
How to use
The power of compounding
Albert Einstein allegedly called compound interest "the eighth wonder of the world." At 7% annual return, money doubles roughly every 10 years (the Rule of 72: 72 ÷ rate = years to double). Starting early matters far more than the amount — a 25-year-old investing £100/month will have far more at 65 than a 35-year-old investing £200/month.
Realistic expectations
UK/global stock market historical average: ~7% annually after inflation. High-yield savings accounts: 4–5%. Fixed-rate bonds: 4–5%. Premium Bonds: ~4.4% average prize rate. Index funds over 20+ years have historically beaten most active funds. Past performance does not guarantee future returns.
Einstein supposedly called compound interest 'the eighth wonder of the world' — though there's no evidence he ever actually said this. The maths is real, though: £1,000 at 7% compounded monthly for 30 years becomes £8,116 — eight times your money, with no extra deposits.
Frequently asked questions
Is the Compound Interest free to use?
Yes, the Compound Interest is completely free. There is no sign-up, no account required, and no limit on how often you can use it.
Does the Compound Interest factor in taxes or fees?
The Compound Interest performs the core calculation only. For final figures, you may need to add applicable taxes, fees, or charges relevant to your situation.
What devices does the Compound Interest work on?
The Compound Interest works on any device with a modern web browser — desktop, laptop, tablet, or phone. It is mobile-friendly and works offline once the page has loaded.