Finance
Compound Interest Calculator
See how an investment grows when interest is earned on both the principal and past interest.
The result shows the final balance and how much of it is interest earned, so the difference between the final balance and the starting amount is the growth from compounding.
Formula
Future value equals principal times one plus the rate divided by compounds per year, raised to compounds times years.
How it works
Compounding frequency matters: monthly compounding grows slightly faster than yearly compounding at the same rate. Enter your starting amount and let the calculator show the final balance and the interest earned.
Worked example
For example, $10,000 at a 6% annual interest rate for 10 years, compounded 12 times per year, gives a future value of $18,193.97 and interest earned of $8,193.97.
FAQs
What does compounds per year mean?
How often interest is added — 12 for monthly, 4 for quarterly, 1 for yearly.
Why does it grow faster than simple interest?
Because each period's interest starts earning interest of its own.
Is tax included?
No, this is a before-tax estimate.
Are these figures financial advice?
No — they are estimates for planning only, not financial advice. Check with a qualified adviser for decisions involving large sums.
Estimates only, not financial advice. Figures are approximate and do not include all fees, taxes, or changing rates unless stated.
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Related guide: How to calculate savings growth: compound interest formula, worked example and growth table
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