Watch money grow with compounding — add regular contributions and choose any compounding frequency.
FV = P(1 + r/n)^(nt) + PMT × [((1 + r/n)^(nt) − 1) ÷ (r/n)]
$10,000 at 7% compounded annually doubles to $20,000 in about 10.24 years thanks to the rule of 72.
Compound interest pays returns on previous returns. Early gains become part of the base earning later gains, so growth accelerates with time — which is why starting early beats contributing more later.
Divide 72 by your annual rate to approximate doubling time: at 8%, money doubles roughly every nine years. Use it as a sanity check against the calculator's output.
Enter the nominal annual rate as APR; the compounding frequency then determines effective yield (APY). The APY calculator converts between them.
Yes — contributions are treated as end-of-period deposits, matching ordinary annuity convention.
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