Compound Interest Calculator
Watch your money multiply — see the real power of starting early and staying consistent.
Investment details
$
$
Growth assumptions
8.0%
%
S&P 500 historical avg ~10%; inflation-adj ~7%
30 yrs
yrs
Inflation (optional)
%
Used to show inflation-adjusted (real) value
Future Value
—
nominal
Total Contributed
—
lump sum + monthly
Investment Gain
—
—% of final value
Real Value (inflation-adj)
—
Effective Real Return
—
Portfolio growth over time
Contributions
Investment gains
—
Rule of 72
At —% annual return, your money doubles roughly every — years. Starting with —, you'd reach — in — doublings over your time horizon.
At —% annual return, your money doubles roughly every — years. Starting with —, you'd reach — in — doublings over your time horizon.
Yearly milestones
| Year | Total Value | Contributed | Gain | Real Value |
|---|