Compound growth calculator
See what a starting pot plus regular monthly saving could grow into — and how much of the result is growth rather than your own money. The teal line is your projection; the grey line is contributions alone.
Your numbers
Projection
Projected pot
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You put in
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Growth
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Illustration only — not a forecast, guarantee or recommendation. Real returns vary year to year and can be negative; invested capital is at risk.
Assumptions and method
- Growth compounds monthly at the annual rate you enter divided by 12; contributions are added at the end of each month.
- No allowance for inflation, tax, or charges — try a rate net of expected fees, or use the fee impact calculator to see what charges do.
- For context: cash savings rates, and long-run diversified investment returns, have historically differed substantially — but past performance is not a guide to the future.
Want the concepts behind the numbers? Read investing basics and ISAs explained.
Reminder: this tool is general education. It doesn't know your circumstances and isn't a personal recommendation. For decisions, consult an FCA-authorised adviser — our toolkit shows how to find one.