Finance calculator

Compound Interest Calculator

Use this compound interest calculator to explore how starting balance, recurring contributions, rate assumptions, and time can affect an estimated future balance.

Calculator

Results

Final balance
$155,163.29
Total contributions
$77,000.00
Estimated growth
$78,163.29

Formula

  • Monthly rate = annual return rate / 12
  • Final balance grows the starting amount and adds each monthly contribution
  • Total contributions = initial amount + monthly contribution x months
  • Estimated growth = final balance - total contributions

Example calculation

With $5,000 to start, $300 added monthly, a 6% annual return assumption, and 20 years, the estimated final balance is about $166,690. Contributions total $77,000, and estimated growth is about $89,690.

FAQ

Is the return rate guaranteed?

No. The return rate is only an assumption for educational modeling. Real investment returns can vary and may be negative.

How often does this compound?

The calculator uses monthly compounding and assumes contributions are added monthly.

Does this include taxes or fees?

No. Taxes, account fees, inflation, and investment costs can materially affect real results.

Educational disclaimer

MoneyHackWise calculators are for educational purposes only and do not provide financial, investment, tax, legal, accounting, lending, or business advice. Results are estimates based on the inputs and assumptions shown.