Compound Interest Calculator
Estimate investment growth from a starting balance, annual return, recurring contributions, and compounding schedule.
How it works
This calculator estimates how a balance may grow when interest or investment returns are periodically added back into the balance. Enter a starting amount, annual return, time horizon, and optional recurring contribution.
The estimate applies the annual rate across the selected compounding schedule. Recurring contributions are added at the beginning or end of each contribution period, depending on the option you choose.
Future value grows as each period's earnings are added to the balance before later periods are calculated.
The breakdown separates starting balance, total contributions, estimated earnings, and final value so you can compare how much of the result comes from deposits versus growth.
Assumptions and limitations
Use this for quick savings, investing, and planning estimates with a steady annual rate and regular contributions. It does not model taxes, fees, inflation, changing returns, market volatility, contribution limits, withdrawal rules, or account-specific rounding.
Results are estimates for planning and are not financial, tax, legal, or investment advice. Compare this estimate with account disclosures and advice from qualified professionals before making decisions.
All calculations happen locally in your browser. Your balances, rates, and planning inputs are not sent to a server.
