Tools · Compound Interest

Compound interest,
visualized.

The most important number in personal finance is time. Plug in your initial amount, monthly contribution, expected return, and horizon. See the hockey stick. Then see what happens if you wait 5 years to start.

7% is a reasonable real (inflation-adjusted) long-run return for a total-market equity portfolio. 10% is a nominal return benchmark. Use what matches your scenario.

FINAL VALUE
$0
TOTAL CONTRIBUTED
$0
GROWTH FROM COMPOUNDING
$0
COST OF WAITING 5 YRS
$0

What this tool assumes
  • Monthly compounding at the annual rate divided by 12.
  • Contributions are added at the end of each month.
  • Rate is assumed constant; real markets compound unevenly.
  • Taxes and fees are not modeled; use the Expense Ratio Impact tool for fee impact.

Not financial advice. Compounds monthly at the annual rate divided by 12. Real returns will vary.

Related

→ Compound Interest Guide → Investing for Beginners → Retirement Planner → Personal Finance Order of Operations
HOW THIS IS CALCULATED

This tool runs entirely in your browser — no data is sent to any server. All formulas use standard financial math. Verify the methodology or inspect the source code in your browser's dev tools.